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diff --git a/vendor/github.com/prometheus/client_golang/LICENSE b/vendor/github.com/prometheus/client_golang/LICENSE
deleted file mode 100644
index 261eeb9..0000000
--- a/vendor/github.com/prometheus/client_golang/LICENSE
+++ /dev/null
@@ -1,201 +0,0 @@
-                                 Apache License
-                           Version 2.0, January 2004
-                        http://www.apache.org/licenses/
-
-   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
-
-   1. Definitions.
-
-      "License" shall mean the terms and conditions for use, reproduction,
-      and distribution as defined by Sections 1 through 9 of this document.
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-      the copyright owner that is granting the License.
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-      other entities that control, are controlled by, or are under common
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-      direction or management of such entity, whether by contract or
-      otherwise, or (ii) ownership of fifty percent (50%) or more of the
-      outstanding shares, or (iii) beneficial ownership of such entity.
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-      "You" (or "Your") shall mean an individual or Legal Entity
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-      form, that is based on (or derived from) the Work and for which the
-      editorial revisions, annotations, elaborations, or other modifications
-      represent, as a whole, an original work of authorship. For the purposes
-      of this License, Derivative Works shall not include works that remain
-      separable from, or merely link (or bind by name) to the interfaces of,
-      the Work and Derivative Works thereof.
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-      "Contribution" shall mean any work of authorship, including
-      the original version of the Work and any modifications or additions
-      to that Work or Derivative Works thereof, that is intentionally
-      submitted to Licensor for inclusion in the Work by the copyright owner
-      or by an individual or Legal Entity authorized to submit on behalf of
-      the copyright owner. For the purposes of this definition, "submitted"
-      means any form of electronic, verbal, or written communication sent
-      to the Licensor or its representatives, including but not limited to
-      communication on electronic mailing lists, source code control systems,
-      and issue tracking systems that are managed by, or on behalf of, the
-      Licensor for the purpose of discussing and improving the Work, but
-      excluding communication that is conspicuously marked or otherwise
-      designated in writing by the copyright owner as "Not a Contribution."
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-      "Contributor" shall mean Licensor and any individual or Legal Entity
-      on behalf of whom a Contribution has been received by Licensor and
-      subsequently incorporated within the Work.
-
-   2. Grant of Copyright License. Subject to the terms and conditions of
-      this License, each Contributor hereby grants to You a perpetual,
-      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
-      copyright license to reproduce, prepare Derivative Works of,
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-      Work and such Derivative Works in Source or Object form.
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-      this License, each Contributor hereby grants to You a perpetual,
-      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
-      (except as stated in this section) patent license to make, have made,
-      use, offer to sell, sell, import, and otherwise transfer the Work,
-      where such license applies only to those patent claims licensable
-      by such Contributor that are necessarily infringed by their
-      Contribution(s) alone or by combination of their Contribution(s)
-      with the Work to which such Contribution(s) was submitted. If You
-      institute patent litigation against any entity (including a
-      cross-claim or counterclaim in a lawsuit) alleging that the Work
-      or a Contribution incorporated within the Work constitutes direct
-      or contributory patent infringement, then any patent licenses
-      granted to You under this License for that Work shall terminate
-      as of the date such litigation is filed.
-
-   4. Redistribution. You may reproduce and distribute copies of the
-      Work or Derivative Works thereof in any medium, with or without
-      modifications, and in Source or Object form, provided that You
-      meet the following conditions:
-
-      (a) You must give any other recipients of the Work or
-          Derivative Works a copy of this License; and
-
-      (b) You must cause any modified files to carry prominent notices
-          stating that You changed the files; and
-
-      (c) You must retain, in the Source form of any Derivative Works
-          that You distribute, all copyright, patent, trademark, and
-          attribution notices from the Source form of the Work,
-          excluding those notices that do not pertain to any part of
-          the Derivative Works; and
-
-      (d) If the Work includes a "NOTICE" text file as part of its
-          distribution, then any Derivative Works that You distribute must
-          include a readable copy of the attribution notices contained
-          within such NOTICE file, excluding those notices that do not
-          pertain to any part of the Derivative Works, in at least one
-          of the following places: within a NOTICE text file distributed
-          as part of the Derivative Works; within the Source form or
-          documentation, if provided along with the Derivative Works; or,
-          within a display generated by the Derivative Works, if and
-          wherever such third-party notices normally appear. The contents
-          of the NOTICE file are for informational purposes only and
-          do not modify the License. You may add Your own attribution
-          notices within Derivative Works that You distribute, alongside
-          or as an addendum to the NOTICE text from the Work, provided
-          that such additional attribution notices cannot be construed
-          as modifying the License.
-
-      You may add Your own copyright statement to Your modifications and
-      may provide additional or different license terms and conditions
-      for use, reproduction, or distribution of Your modifications, or
-      for any such Derivative Works as a whole, provided Your use,
-      reproduction, and distribution of the Work otherwise complies with
-      the conditions stated in this License.
-
-   5. Submission of Contributions. Unless You explicitly state otherwise,
-      any Contribution intentionally submitted for inclusion in the Work
-      by You to the Licensor shall be under the terms and conditions of
-      this License, without any additional terms or conditions.
-      Notwithstanding the above, nothing herein shall supersede or modify
-      the terms of any separate license agreement you may have executed
-      with Licensor regarding such Contributions.
-
-   6. Trademarks. This License does not grant permission to use the trade
-      names, trademarks, service marks, or product names of the Licensor,
-      except as required for reasonable and customary use in describing the
-      origin of the Work and reproducing the content of the NOTICE file.
-
-   7. Disclaimer of Warranty. Unless required by applicable law or
-      agreed to in writing, Licensor provides the Work (and each
-      Contributor provides its Contributions) on an "AS IS" BASIS,
-      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
-      implied, including, without limitation, any warranties or conditions
-      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
-      PARTICULAR PURPOSE. You are solely responsible for determining the
-      appropriateness of using or redistributing the Work and assume any
-      risks associated with Your exercise of permissions under this License.
-
-   8. Limitation of Liability. In no event and under no legal theory,
-      whether in tort (including negligence), contract, or otherwise,
-      unless required by applicable law (such as deliberate and grossly
-      negligent acts) or agreed to in writing, shall any Contributor be
-      liable to You for damages, including any direct, indirect, special,
-      incidental, or consequential damages of any character arising as a
-      result of this License or out of the use or inability to use the
-      Work (including but not limited to damages for loss of goodwill,
-      work stoppage, computer failure or malfunction, or any and all
-      other commercial damages or losses), even if such Contributor
-      has been advised of the possibility of such damages.
-
-   9. Accepting Warranty or Additional Liability. While redistributing
-      the Work or Derivative Works thereof, You may choose to offer,
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-      or other liability obligations and/or rights consistent with this
-      License. However, in accepting such obligations, You may act only
-      on Your own behalf and on Your sole responsibility, not on behalf
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diff --git a/vendor/github.com/prometheus/client_golang/NOTICE b/vendor/github.com/prometheus/client_golang/NOTICE
deleted file mode 100644
index dd878a3..0000000
--- a/vendor/github.com/prometheus/client_golang/NOTICE
+++ /dev/null
@@ -1,23 +0,0 @@
-Prometheus instrumentation library for Go applications
-Copyright 2012-2015 The Prometheus Authors
-
-This product includes software developed at
-SoundCloud Ltd. (http://soundcloud.com/).
-
-
-The following components are included in this product:
-
-perks - a fork of https://github.com/bmizerany/perks
-https://github.com/beorn7/perks
-Copyright 2013-2015 Blake Mizerany, Björn Rabenstein
-See https://github.com/beorn7/perks/blob/master/README.md for license details.
-
-Go support for Protocol Buffers - Google's data interchange format
-http://github.com/golang/protobuf/
-Copyright 2010 The Go Authors
-See source code for license details.
-
-Support for streaming Protocol Buffer messages for the Go language (golang).
-https://github.com/matttproud/golang_protobuf_extensions
-Copyright 2013 Matt T. Proud
-Licensed under the Apache License, Version 2.0
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/README.md b/vendor/github.com/prometheus/client_golang/prometheus/README.md
deleted file mode 100644
index 44986bf..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/README.md
+++ /dev/null
@@ -1 +0,0 @@
-See [![go-doc](https://godoc.org/github.com/prometheus/client_golang/prometheus?status.svg)](https://godoc.org/github.com/prometheus/client_golang/prometheus).
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/collector.go b/vendor/github.com/prometheus/client_golang/prometheus/collector.go
deleted file mode 100644
index 3c9bae2..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/collector.go
+++ /dev/null
@@ -1,86 +0,0 @@
-// Copyright 2014 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-// Collector is the interface implemented by anything that can be used by
-// Prometheus to collect metrics. A Collector has to be registered for
-// collection. See Registerer.Register.
-//
-// The stock metrics provided by this package (Gauge, Counter, Summary,
-// Histogram, Untyped) are also Collectors (which only ever collect one metric,
-// namely itself). An implementer of Collector may, however, collect multiple
-// metrics in a coordinated fashion and/or create metrics on the fly. Examples
-// for collectors already implemented in this library are the metric vectors
-// (i.e. collection of multiple instances of the same Metric but with different
-// label values) like GaugeVec or SummaryVec, and the ExpvarCollector.
-type Collector interface {
-	// Describe sends the super-set of all possible descriptors of metrics
-	// collected by this Collector to the provided channel and returns once
-	// the last descriptor has been sent. The sent descriptors fulfill the
-	// consistency and uniqueness requirements described in the Desc
-	// documentation.
-	//
-	// It is valid if one and the same Collector sends duplicate
-	// descriptors. Those duplicates are simply ignored. However, two
-	// different Collectors must not send duplicate descriptors.
-	//
-	// Sending no descriptor at all marks the Collector as “unchecked”,
-	// i.e. no checks will be performed at registration time, and the
-	// Collector may yield any Metric it sees fit in its Collect method.
-	//
-	// This method idempotently sends the same descriptors throughout the
-	// lifetime of the Collector.
-	//
-	// If a Collector encounters an error while executing this method, it
-	// must send an invalid descriptor (created with NewInvalidDesc) to
-	// signal the error to the registry.
-	Describe(chan<- *Desc)
-	// Collect is called by the Prometheus registry when collecting
-	// metrics. The implementation sends each collected metric via the
-	// provided channel and returns once the last metric has been sent. The
-	// descriptor of each sent metric is one of those returned by Describe
-	// (unless the Collector is unchecked, see above). Returned metrics that
-	// share the same descriptor must differ in their variable label
-	// values.
-	//
-	// This method may be called concurrently and must therefore be
-	// implemented in a concurrency safe way. Blocking occurs at the expense
-	// of total performance of rendering all registered metrics. Ideally,
-	// Collector implementations support concurrent readers.
-	Collect(chan<- Metric)
-}
-
-// selfCollector implements Collector for a single Metric so that the Metric
-// collects itself. Add it as an anonymous field to a struct that implements
-// Metric, and call init with the Metric itself as an argument.
-type selfCollector struct {
-	self Metric
-}
-
-// init provides the selfCollector with a reference to the metric it is supposed
-// to collect. It is usually called within the factory function to create a
-// metric. See example.
-func (c *selfCollector) init(self Metric) {
-	c.self = self
-}
-
-// Describe implements Collector.
-func (c *selfCollector) Describe(ch chan<- *Desc) {
-	ch <- c.self.Desc()
-}
-
-// Collect implements Collector.
-func (c *selfCollector) Collect(ch chan<- Metric) {
-	ch <- c.self
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/counter.go b/vendor/github.com/prometheus/client_golang/prometheus/counter.go
deleted file mode 100644
index 765e455..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/counter.go
+++ /dev/null
@@ -1,277 +0,0 @@
-// Copyright 2014 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"errors"
-	"math"
-	"sync/atomic"
-
-	dto "github.com/prometheus/client_model/go"
-)
-
-// Counter is a Metric that represents a single numerical value that only ever
-// goes up. That implies that it cannot be used to count items whose number can
-// also go down, e.g. the number of currently running goroutines. Those
-// "counters" are represented by Gauges.
-//
-// A Counter is typically used to count requests served, tasks completed, errors
-// occurred, etc.
-//
-// To create Counter instances, use NewCounter.
-type Counter interface {
-	Metric
-	Collector
-
-	// Inc increments the counter by 1. Use Add to increment it by arbitrary
-	// non-negative values.
-	Inc()
-	// Add adds the given value to the counter. It panics if the value is <
-	// 0.
-	Add(float64)
-}
-
-// CounterOpts is an alias for Opts. See there for doc comments.
-type CounterOpts Opts
-
-// NewCounter creates a new Counter based on the provided CounterOpts.
-//
-// The returned implementation tracks the counter value in two separate
-// variables, a float64 and a uint64. The latter is used to track calls of the
-// Inc method and calls of the Add method with a value that can be represented
-// as a uint64. This allows atomic increments of the counter with optimal
-// performance. (It is common to have an Inc call in very hot execution paths.)
-// Both internal tracking values are added up in the Write method. This has to
-// be taken into account when it comes to precision and overflow behavior.
-func NewCounter(opts CounterOpts) Counter {
-	desc := NewDesc(
-		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
-		opts.Help,
-		nil,
-		opts.ConstLabels,
-	)
-	result := &counter{desc: desc, labelPairs: desc.constLabelPairs}
-	result.init(result) // Init self-collection.
-	return result
-}
-
-type counter struct {
-	// valBits contains the bits of the represented float64 value, while
-	// valInt stores values that are exact integers. Both have to go first
-	// in the struct to guarantee alignment for atomic operations.
-	// http://golang.org/pkg/sync/atomic/#pkg-note-BUG
-	valBits uint64
-	valInt  uint64
-
-	selfCollector
-	desc *Desc
-
-	labelPairs []*dto.LabelPair
-}
-
-func (c *counter) Desc() *Desc {
-	return c.desc
-}
-
-func (c *counter) Add(v float64) {
-	if v < 0 {
-		panic(errors.New("counter cannot decrease in value"))
-	}
-	ival := uint64(v)
-	if float64(ival) == v {
-		atomic.AddUint64(&c.valInt, ival)
-		return
-	}
-
-	for {
-		oldBits := atomic.LoadUint64(&c.valBits)
-		newBits := math.Float64bits(math.Float64frombits(oldBits) + v)
-		if atomic.CompareAndSwapUint64(&c.valBits, oldBits, newBits) {
-			return
-		}
-	}
-}
-
-func (c *counter) Inc() {
-	atomic.AddUint64(&c.valInt, 1)
-}
-
-func (c *counter) Write(out *dto.Metric) error {
-	fval := math.Float64frombits(atomic.LoadUint64(&c.valBits))
-	ival := atomic.LoadUint64(&c.valInt)
-	val := fval + float64(ival)
-
-	return populateMetric(CounterValue, val, c.labelPairs, out)
-}
-
-// CounterVec is a Collector that bundles a set of Counters that all share the
-// same Desc, but have different values for their variable labels. This is used
-// if you want to count the same thing partitioned by various dimensions
-// (e.g. number of HTTP requests, partitioned by response code and
-// method). Create instances with NewCounterVec.
-type CounterVec struct {
-	*metricVec
-}
-
-// NewCounterVec creates a new CounterVec based on the provided CounterOpts and
-// partitioned by the given label names.
-func NewCounterVec(opts CounterOpts, labelNames []string) *CounterVec {
-	desc := NewDesc(
-		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
-		opts.Help,
-		labelNames,
-		opts.ConstLabels,
-	)
-	return &CounterVec{
-		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
-			if len(lvs) != len(desc.variableLabels) {
-				panic(errInconsistentCardinality)
-			}
-			result := &counter{desc: desc, labelPairs: makeLabelPairs(desc, lvs)}
-			result.init(result) // Init self-collection.
-			return result
-		}),
-	}
-}
-
-// GetMetricWithLabelValues returns the Counter for the given slice of label
-// values (same order as the VariableLabels in Desc). If that combination of
-// label values is accessed for the first time, a new Counter is created.
-//
-// It is possible to call this method without using the returned Counter to only
-// create the new Counter but leave it at its starting value 0. See also the
-// SummaryVec example.
-//
-// Keeping the Counter for later use is possible (and should be considered if
-// performance is critical), but keep in mind that Reset, DeleteLabelValues and
-// Delete can be used to delete the Counter from the CounterVec. In that case,
-// the Counter will still exist, but it will not be exported anymore, even if a
-// Counter with the same label values is created later.
-//
-// An error is returned if the number of label values is not the same as the
-// number of VariableLabels in Desc (minus any curried labels).
-//
-// Note that for more than one label value, this method is prone to mistakes
-// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
-// an alternative to avoid that type of mistake. For higher label numbers, the
-// latter has a much more readable (albeit more verbose) syntax, but it comes
-// with a performance overhead (for creating and processing the Labels map).
-// See also the GaugeVec example.
-func (v *CounterVec) GetMetricWithLabelValues(lvs ...string) (Counter, error) {
-	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
-	if metric != nil {
-		return metric.(Counter), err
-	}
-	return nil, err
-}
-
-// GetMetricWith returns the Counter for the given Labels map (the label names
-// must match those of the VariableLabels in Desc). If that label map is
-// accessed for the first time, a new Counter is created. Implications of
-// creating a Counter without using it and keeping the Counter for later use are
-// the same as for GetMetricWithLabelValues.
-//
-// An error is returned if the number and names of the Labels are inconsistent
-// with those of the VariableLabels in Desc (minus any curried labels).
-//
-// This method is used for the same purpose as
-// GetMetricWithLabelValues(...string). See there for pros and cons of the two
-// methods.
-func (v *CounterVec) GetMetricWith(labels Labels) (Counter, error) {
-	metric, err := v.metricVec.getMetricWith(labels)
-	if metric != nil {
-		return metric.(Counter), err
-	}
-	return nil, err
-}
-
-// WithLabelValues works as GetMetricWithLabelValues, but panics where
-// GetMetricWithLabelValues would have returned an error. Not returning an
-// error allows shortcuts like
-//     myVec.WithLabelValues("404", "GET").Add(42)
-func (v *CounterVec) WithLabelValues(lvs ...string) Counter {
-	c, err := v.GetMetricWithLabelValues(lvs...)
-	if err != nil {
-		panic(err)
-	}
-	return c
-}
-
-// With works as GetMetricWith, but panics where GetMetricWithLabels would have
-// returned an error. Not returning an error allows shortcuts like
-//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42)
-func (v *CounterVec) With(labels Labels) Counter {
-	c, err := v.GetMetricWith(labels)
-	if err != nil {
-		panic(err)
-	}
-	return c
-}
-
-// CurryWith returns a vector curried with the provided labels, i.e. the
-// returned vector has those labels pre-set for all labeled operations performed
-// on it. The cardinality of the curried vector is reduced accordingly. The
-// order of the remaining labels stays the same (just with the curried labels
-// taken out of the sequence – which is relevant for the
-// (GetMetric)WithLabelValues methods). It is possible to curry a curried
-// vector, but only with labels not yet used for currying before.
-//
-// The metrics contained in the CounterVec are shared between the curried and
-// uncurried vectors. They are just accessed differently. Curried and uncurried
-// vectors behave identically in terms of collection. Only one must be
-// registered with a given registry (usually the uncurried version). The Reset
-// method deletes all metrics, even if called on a curried vector.
-func (v *CounterVec) CurryWith(labels Labels) (*CounterVec, error) {
-	vec, err := v.curryWith(labels)
-	if vec != nil {
-		return &CounterVec{vec}, err
-	}
-	return nil, err
-}
-
-// MustCurryWith works as CurryWith but panics where CurryWith would have
-// returned an error.
-func (v *CounterVec) MustCurryWith(labels Labels) *CounterVec {
-	vec, err := v.CurryWith(labels)
-	if err != nil {
-		panic(err)
-	}
-	return vec
-}
-
-// CounterFunc is a Counter whose value is determined at collect time by calling a
-// provided function.
-//
-// To create CounterFunc instances, use NewCounterFunc.
-type CounterFunc interface {
-	Metric
-	Collector
-}
-
-// NewCounterFunc creates a new CounterFunc based on the provided
-// CounterOpts. The value reported is determined by calling the given function
-// from within the Write method. Take into account that metric collection may
-// happen concurrently. If that results in concurrent calls to Write, like in
-// the case where a CounterFunc is directly registered with Prometheus, the
-// provided function must be concurrency-safe. The function should also honor
-// the contract for a Counter (values only go up, not down), but compliance will
-// not be checked.
-func NewCounterFunc(opts CounterOpts, function func() float64) CounterFunc {
-	return newValueFunc(NewDesc(
-		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
-		opts.Help,
-		nil,
-		opts.ConstLabels,
-	), CounterValue, function)
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/desc.go b/vendor/github.com/prometheus/client_golang/prometheus/desc.go
deleted file mode 100644
index 4a755b0..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/desc.go
+++ /dev/null
@@ -1,188 +0,0 @@
-// Copyright 2016 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"errors"
-	"fmt"
-	"sort"
-	"strings"
-
-	"github.com/golang/protobuf/proto"
-	"github.com/prometheus/common/model"
-
-	dto "github.com/prometheus/client_model/go"
-)
-
-// Desc is the descriptor used by every Prometheus Metric. It is essentially
-// the immutable meta-data of a Metric. The normal Metric implementations
-// included in this package manage their Desc under the hood. Users only have to
-// deal with Desc if they use advanced features like the ExpvarCollector or
-// custom Collectors and Metrics.
-//
-// Descriptors registered with the same registry have to fulfill certain
-// consistency and uniqueness criteria if they share the same fully-qualified
-// name: They must have the same help string and the same label names (aka label
-// dimensions) in each, constLabels and variableLabels, but they must differ in
-// the values of the constLabels.
-//
-// Descriptors that share the same fully-qualified names and the same label
-// values of their constLabels are considered equal.
-//
-// Use NewDesc to create new Desc instances.
-type Desc struct {
-	// fqName has been built from Namespace, Subsystem, and Name.
-	fqName string
-	// help provides some helpful information about this metric.
-	help string
-	// constLabelPairs contains precalculated DTO label pairs based on
-	// the constant labels.
-	constLabelPairs []*dto.LabelPair
-	// VariableLabels contains names of labels for which the metric
-	// maintains variable values.
-	variableLabels []string
-	// id is a hash of the values of the ConstLabels and fqName. This
-	// must be unique among all registered descriptors and can therefore be
-	// used as an identifier of the descriptor.
-	id uint64
-	// dimHash is a hash of the label names (preset and variable) and the
-	// Help string. Each Desc with the same fqName must have the same
-	// dimHash.
-	dimHash uint64
-	// err is an error that occurred during construction. It is reported on
-	// registration time.
-	err error
-}
-
-// NewDesc allocates and initializes a new Desc. Errors are recorded in the Desc
-// and will be reported on registration time. variableLabels and constLabels can
-// be nil if no such labels should be set. fqName and help must not be empty.
-//
-// variableLabels only contain the label names. Their label values are variable
-// and therefore not part of the Desc. (They are managed within the Metric.)
-//
-// For constLabels, the label values are constant. Therefore, they are fully
-// specified in the Desc. See the Collector example for a usage pattern.
-func NewDesc(fqName, help string, variableLabels []string, constLabels Labels) *Desc {
-	d := &Desc{
-		fqName:         fqName,
-		help:           help,
-		variableLabels: variableLabels,
-	}
-	if help == "" {
-		d.err = errors.New("empty help string")
-		return d
-	}
-	if !model.IsValidMetricName(model.LabelValue(fqName)) {
-		d.err = fmt.Errorf("%q is not a valid metric name", fqName)
-		return d
-	}
-	// labelValues contains the label values of const labels (in order of
-	// their sorted label names) plus the fqName (at position 0).
-	labelValues := make([]string, 1, len(constLabels)+1)
-	labelValues[0] = fqName
-	labelNames := make([]string, 0, len(constLabels)+len(variableLabels))
-	labelNameSet := map[string]struct{}{}
-	// First add only the const label names and sort them...
-	for labelName := range constLabels {
-		if !checkLabelName(labelName) {
-			d.err = fmt.Errorf("%q is not a valid label name", labelName)
-			return d
-		}
-		labelNames = append(labelNames, labelName)
-		labelNameSet[labelName] = struct{}{}
-	}
-	sort.Strings(labelNames)
-	// ... so that we can now add const label values in the order of their names.
-	for _, labelName := range labelNames {
-		labelValues = append(labelValues, constLabels[labelName])
-	}
-	// Validate the const label values. They can't have a wrong cardinality, so
-	// use in len(labelValues) as expectedNumberOfValues.
-	if err := validateLabelValues(labelValues, len(labelValues)); err != nil {
-		d.err = err
-		return d
-	}
-	// Now add the variable label names, but prefix them with something that
-	// cannot be in a regular label name. That prevents matching the label
-	// dimension with a different mix between preset and variable labels.
-	for _, labelName := range variableLabels {
-		if !checkLabelName(labelName) {
-			d.err = fmt.Errorf("%q is not a valid label name", labelName)
-			return d
-		}
-		labelNames = append(labelNames, "$"+labelName)
-		labelNameSet[labelName] = struct{}{}
-	}
-	if len(labelNames) != len(labelNameSet) {
-		d.err = errors.New("duplicate label names")
-		return d
-	}
-
-	vh := hashNew()
-	for _, val := range labelValues {
-		vh = hashAdd(vh, val)
-		vh = hashAddByte(vh, separatorByte)
-	}
-	d.id = vh
-	// Sort labelNames so that order doesn't matter for the hash.
-	sort.Strings(labelNames)
-	// Now hash together (in this order) the help string and the sorted
-	// label names.
-	lh := hashNew()
-	lh = hashAdd(lh, help)
-	lh = hashAddByte(lh, separatorByte)
-	for _, labelName := range labelNames {
-		lh = hashAdd(lh, labelName)
-		lh = hashAddByte(lh, separatorByte)
-	}
-	d.dimHash = lh
-
-	d.constLabelPairs = make([]*dto.LabelPair, 0, len(constLabels))
-	for n, v := range constLabels {
-		d.constLabelPairs = append(d.constLabelPairs, &dto.LabelPair{
-			Name:  proto.String(n),
-			Value: proto.String(v),
-		})
-	}
-	sort.Sort(LabelPairSorter(d.constLabelPairs))
-	return d
-}
-
-// NewInvalidDesc returns an invalid descriptor, i.e. a descriptor with the
-// provided error set. If a collector returning such a descriptor is registered,
-// registration will fail with the provided error. NewInvalidDesc can be used by
-// a Collector to signal inability to describe itself.
-func NewInvalidDesc(err error) *Desc {
-	return &Desc{
-		err: err,
-	}
-}
-
-func (d *Desc) String() string {
-	lpStrings := make([]string, 0, len(d.constLabelPairs))
-	for _, lp := range d.constLabelPairs {
-		lpStrings = append(
-			lpStrings,
-			fmt.Sprintf("%s=%q", lp.GetName(), lp.GetValue()),
-		)
-	}
-	return fmt.Sprintf(
-		"Desc{fqName: %q, help: %q, constLabels: {%s}, variableLabels: %v}",
-		d.fqName,
-		d.help,
-		strings.Join(lpStrings, ","),
-		d.variableLabels,
-	)
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/doc.go b/vendor/github.com/prometheus/client_golang/prometheus/doc.go
deleted file mode 100644
index 5d9525d..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/doc.go
+++ /dev/null
@@ -1,201 +0,0 @@
-// Copyright 2014 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Package prometheus is the core instrumentation package. It provides metrics
-// primitives to instrument code for monitoring. It also offers a registry for
-// metrics. Sub-packages allow to expose the registered metrics via HTTP
-// (package promhttp) or push them to a Pushgateway (package push). There is
-// also a sub-package promauto, which provides metrics constructors with
-// automatic registration.
-//
-// All exported functions and methods are safe to be used concurrently unless
-// specified otherwise.
-//
-// A Basic Example
-//
-// As a starting point, a very basic usage example:
-//
-//    package main
-//
-//    import (
-//    	"log"
-//    	"net/http"
-//
-//    	"github.com/prometheus/client_golang/prometheus"
-//    	"github.com/prometheus/client_golang/prometheus/promhttp"
-//    )
-//
-//    var (
-//    	cpuTemp = prometheus.NewGauge(prometheus.GaugeOpts{
-//    		Name: "cpu_temperature_celsius",
-//    		Help: "Current temperature of the CPU.",
-//    	})
-//    	hdFailures = prometheus.NewCounterVec(
-//    		prometheus.CounterOpts{
-//    			Name: "hd_errors_total",
-//    			Help: "Number of hard-disk errors.",
-//    		},
-//    		[]string{"device"},
-//    	)
-//    )
-//
-//    func init() {
-//    	// Metrics have to be registered to be exposed:
-//    	prometheus.MustRegister(cpuTemp)
-//    	prometheus.MustRegister(hdFailures)
-//    }
-//
-//    func main() {
-//    	cpuTemp.Set(65.3)
-//    	hdFailures.With(prometheus.Labels{"device":"/dev/sda"}).Inc()
-//
-//    	// The Handler function provides a default handler to expose metrics
-//    	// via an HTTP server. "/metrics" is the usual endpoint for that.
-//    	http.Handle("/metrics", promhttp.Handler())
-//    	log.Fatal(http.ListenAndServe(":8080", nil))
-//    }
-//
-//
-// This is a complete program that exports two metrics, a Gauge and a Counter,
-// the latter with a label attached to turn it into a (one-dimensional) vector.
-//
-// Metrics
-//
-// The number of exported identifiers in this package might appear a bit
-// overwhelming. However, in addition to the basic plumbing shown in the example
-// above, you only need to understand the different metric types and their
-// vector versions for basic usage. Furthermore, if you are not concerned with
-// fine-grained control of when and how to register metrics with the registry,
-// have a look at the promauto package, which will effectively allow you to
-// ignore registration altogether in simple cases.
-//
-// Above, you have already touched the Counter and the Gauge. There are two more
-// advanced metric types: the Summary and Histogram. A more thorough description
-// of those four metric types can be found in the Prometheus docs:
-// https://prometheus.io/docs/concepts/metric_types/
-//
-// A fifth "type" of metric is Untyped. It behaves like a Gauge, but signals the
-// Prometheus server not to assume anything about its type.
-//
-// In addition to the fundamental metric types Gauge, Counter, Summary,
-// Histogram, and Untyped, a very important part of the Prometheus data model is
-// the partitioning of samples along dimensions called labels, which results in
-// metric vectors. The fundamental types are GaugeVec, CounterVec, SummaryVec,
-// HistogramVec, and UntypedVec.
-//
-// While only the fundamental metric types implement the Metric interface, both
-// the metrics and their vector versions implement the Collector interface. A
-// Collector manages the collection of a number of Metrics, but for convenience,
-// a Metric can also “collect itself”. Note that Gauge, Counter, Summary,
-// Histogram, and Untyped are interfaces themselves while GaugeVec, CounterVec,
-// SummaryVec, HistogramVec, and UntypedVec are not.
-//
-// To create instances of Metrics and their vector versions, you need a suitable
-// …Opts struct, i.e. GaugeOpts, CounterOpts, SummaryOpts, HistogramOpts, or
-// UntypedOpts.
-//
-// Custom Collectors and constant Metrics
-//
-// While you could create your own implementations of Metric, most likely you
-// will only ever implement the Collector interface on your own. At a first
-// glance, a custom Collector seems handy to bundle Metrics for common
-// registration (with the prime example of the different metric vectors above,
-// which bundle all the metrics of the same name but with different labels).
-//
-// There is a more involved use case, too: If you already have metrics
-// available, created outside of the Prometheus context, you don't need the
-// interface of the various Metric types. You essentially want to mirror the
-// existing numbers into Prometheus Metrics during collection. An own
-// implementation of the Collector interface is perfect for that. You can create
-// Metric instances “on the fly” using NewConstMetric, NewConstHistogram, and
-// NewConstSummary (and their respective Must… versions). That will happen in
-// the Collect method. The Describe method has to return separate Desc
-// instances, representative of the “throw-away” metrics to be created later.
-// NewDesc comes in handy to create those Desc instances. Alternatively, you
-// could return no Desc at all, which will marke the Collector “unchecked”.  No
-// checks are porformed at registration time, but metric consistency will still
-// be ensured at scrape time, i.e. any inconsistencies will lead to scrape
-// errors. Thus, with unchecked Collectors, the responsibility to not collect
-// metrics that lead to inconsistencies in the total scrape result lies with the
-// implementer of the Collector. While this is not a desirable state, it is
-// sometimes necessary. The typical use case is a situatios where the exact
-// metrics to be returned by a Collector cannot be predicted at registration
-// time, but the implementer has sufficient knowledge of the whole system to
-// guarantee metric consistency.
-//
-// The Collector example illustrates the use case. You can also look at the
-// source code of the processCollector (mirroring process metrics), the
-// goCollector (mirroring Go metrics), or the expvarCollector (mirroring expvar
-// metrics) as examples that are used in this package itself.
-//
-// If you just need to call a function to get a single float value to collect as
-// a metric, GaugeFunc, CounterFunc, or UntypedFunc might be interesting
-// shortcuts.
-//
-// Advanced Uses of the Registry
-//
-// While MustRegister is the by far most common way of registering a Collector,
-// sometimes you might want to handle the errors the registration might cause.
-// As suggested by the name, MustRegister panics if an error occurs. With the
-// Register function, the error is returned and can be handled.
-//
-// An error is returned if the registered Collector is incompatible or
-// inconsistent with already registered metrics. The registry aims for
-// consistency of the collected metrics according to the Prometheus data model.
-// Inconsistencies are ideally detected at registration time, not at collect
-// time. The former will usually be detected at start-up time of a program,
-// while the latter will only happen at scrape time, possibly not even on the
-// first scrape if the inconsistency only becomes relevant later. That is the
-// main reason why a Collector and a Metric have to describe themselves to the
-// registry.
-//
-// So far, everything we did operated on the so-called default registry, as it
-// can be found in the global DefaultRegisterer variable. With NewRegistry, you
-// can create a custom registry, or you can even implement the Registerer or
-// Gatherer interfaces yourself. The methods Register and Unregister work in the
-// same way on a custom registry as the global functions Register and Unregister
-// on the default registry.
-//
-// There are a number of uses for custom registries: You can use registries with
-// special properties, see NewPedanticRegistry. You can avoid global state, as
-// it is imposed by the DefaultRegisterer. You can use multiple registries at
-// the same time to expose different metrics in different ways.  You can use
-// separate registries for testing purposes.
-//
-// Also note that the DefaultRegisterer comes registered with a Collector for Go
-// runtime metrics (via NewGoCollector) and a Collector for process metrics (via
-// NewProcessCollector). With a custom registry, you are in control and decide
-// yourself about the Collectors to register.
-//
-// HTTP Exposition
-//
-// The Registry implements the Gatherer interface. The caller of the Gather
-// method can then expose the gathered metrics in some way. Usually, the metrics
-// are served via HTTP on the /metrics endpoint. That's happening in the example
-// above. The tools to expose metrics via HTTP are in the promhttp sub-package.
-// (The top-level functions in the prometheus package are deprecated.)
-//
-// Pushing to the Pushgateway
-//
-// Function for pushing to the Pushgateway can be found in the push sub-package.
-//
-// Graphite Bridge
-//
-// Functions and examples to push metrics from a Gatherer to Graphite can be
-// found in the graphite sub-package.
-//
-// Other Means of Exposition
-//
-// More ways of exposing metrics can easily be added by following the approaches
-// of the existing implementations.
-package prometheus
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/expvar_collector.go b/vendor/github.com/prometheus/client_golang/prometheus/expvar_collector.go
deleted file mode 100644
index 18a99d5..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/expvar_collector.go
+++ /dev/null
@@ -1,119 +0,0 @@
-// Copyright 2014 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"encoding/json"
-	"expvar"
-)
-
-type expvarCollector struct {
-	exports map[string]*Desc
-}
-
-// NewExpvarCollector returns a newly allocated expvar Collector that still has
-// to be registered with a Prometheus registry.
-//
-// An expvar Collector collects metrics from the expvar interface. It provides a
-// quick way to expose numeric values that are already exported via expvar as
-// Prometheus metrics. Note that the data models of expvar and Prometheus are
-// fundamentally different, and that the expvar Collector is inherently slower
-// than native Prometheus metrics. Thus, the expvar Collector is probably great
-// for experiments and prototying, but you should seriously consider a more
-// direct implementation of Prometheus metrics for monitoring production
-// systems.
-//
-// The exports map has the following meaning:
-//
-// The keys in the map correspond to expvar keys, i.e. for every expvar key you
-// want to export as Prometheus metric, you need an entry in the exports
-// map. The descriptor mapped to each key describes how to export the expvar
-// value. It defines the name and the help string of the Prometheus metric
-// proxying the expvar value. The type will always be Untyped.
-//
-// For descriptors without variable labels, the expvar value must be a number or
-// a bool. The number is then directly exported as the Prometheus sample
-// value. (For a bool, 'false' translates to 0 and 'true' to 1). Expvar values
-// that are not numbers or bools are silently ignored.
-//
-// If the descriptor has one variable label, the expvar value must be an expvar
-// map. The keys in the expvar map become the various values of the one
-// Prometheus label. The values in the expvar map must be numbers or bools again
-// as above.
-//
-// For descriptors with more than one variable label, the expvar must be a
-// nested expvar map, i.e. where the values of the topmost map are maps again
-// etc. until a depth is reached that corresponds to the number of labels. The
-// leaves of that structure must be numbers or bools as above to serve as the
-// sample values.
-//
-// Anything that does not fit into the scheme above is silently ignored.
-func NewExpvarCollector(exports map[string]*Desc) Collector {
-	return &expvarCollector{
-		exports: exports,
-	}
-}
-
-// Describe implements Collector.
-func (e *expvarCollector) Describe(ch chan<- *Desc) {
-	for _, desc := range e.exports {
-		ch <- desc
-	}
-}
-
-// Collect implements Collector.
-func (e *expvarCollector) Collect(ch chan<- Metric) {
-	for name, desc := range e.exports {
-		var m Metric
-		expVar := expvar.Get(name)
-		if expVar == nil {
-			continue
-		}
-		var v interface{}
-		labels := make([]string, len(desc.variableLabels))
-		if err := json.Unmarshal([]byte(expVar.String()), &v); err != nil {
-			ch <- NewInvalidMetric(desc, err)
-			continue
-		}
-		var processValue func(v interface{}, i int)
-		processValue = func(v interface{}, i int) {
-			if i >= len(labels) {
-				copiedLabels := append(make([]string, 0, len(labels)), labels...)
-				switch v := v.(type) {
-				case float64:
-					m = MustNewConstMetric(desc, UntypedValue, v, copiedLabels...)
-				case bool:
-					if v {
-						m = MustNewConstMetric(desc, UntypedValue, 1, copiedLabels...)
-					} else {
-						m = MustNewConstMetric(desc, UntypedValue, 0, copiedLabels...)
-					}
-				default:
-					return
-				}
-				ch <- m
-				return
-			}
-			vm, ok := v.(map[string]interface{})
-			if !ok {
-				return
-			}
-			for lv, val := range vm {
-				labels[i] = lv
-				processValue(val, i+1)
-			}
-		}
-		processValue(v, 0)
-	}
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/fnv.go b/vendor/github.com/prometheus/client_golang/prometheus/fnv.go
deleted file mode 100644
index 3d383a7..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/fnv.go
+++ /dev/null
@@ -1,42 +0,0 @@
-// Copyright 2018 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-// Inline and byte-free variant of hash/fnv's fnv64a.
-
-const (
-	offset64 = 14695981039346656037
-	prime64  = 1099511628211
-)
-
-// hashNew initializies a new fnv64a hash value.
-func hashNew() uint64 {
-	return offset64
-}
-
-// hashAdd adds a string to a fnv64a hash value, returning the updated hash.
-func hashAdd(h uint64, s string) uint64 {
-	for i := 0; i < len(s); i++ {
-		h ^= uint64(s[i])
-		h *= prime64
-	}
-	return h
-}
-
-// hashAddByte adds a byte to a fnv64a hash value, returning the updated hash.
-func hashAddByte(h uint64, b byte) uint64 {
-	h ^= uint64(b)
-	h *= prime64
-	return h
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/gauge.go b/vendor/github.com/prometheus/client_golang/prometheus/gauge.go
deleted file mode 100644
index 17c72d7..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/gauge.go
+++ /dev/null
@@ -1,286 +0,0 @@
-// Copyright 2014 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"math"
-	"sync/atomic"
-	"time"
-
-	dto "github.com/prometheus/client_model/go"
-)
-
-// Gauge is a Metric that represents a single numerical value that can
-// arbitrarily go up and down.
-//
-// A Gauge is typically used for measured values like temperatures or current
-// memory usage, but also "counts" that can go up and down, like the number of
-// running goroutines.
-//
-// To create Gauge instances, use NewGauge.
-type Gauge interface {
-	Metric
-	Collector
-
-	// Set sets the Gauge to an arbitrary value.
-	Set(float64)
-	// Inc increments the Gauge by 1. Use Add to increment it by arbitrary
-	// values.
-	Inc()
-	// Dec decrements the Gauge by 1. Use Sub to decrement it by arbitrary
-	// values.
-	Dec()
-	// Add adds the given value to the Gauge. (The value can be negative,
-	// resulting in a decrease of the Gauge.)
-	Add(float64)
-	// Sub subtracts the given value from the Gauge. (The value can be
-	// negative, resulting in an increase of the Gauge.)
-	Sub(float64)
-
-	// SetToCurrentTime sets the Gauge to the current Unix time in seconds.
-	SetToCurrentTime()
-}
-
-// GaugeOpts is an alias for Opts. See there for doc comments.
-type GaugeOpts Opts
-
-// NewGauge creates a new Gauge based on the provided GaugeOpts.
-//
-// The returned implementation is optimized for a fast Set method. If you have a
-// choice for managing the value of a Gauge via Set vs. Inc/Dec/Add/Sub, pick
-// the former. For example, the Inc method of the returned Gauge is slower than
-// the Inc method of a Counter returned by NewCounter. This matches the typical
-// scenarios for Gauges and Counters, where the former tends to be Set-heavy and
-// the latter Inc-heavy.
-func NewGauge(opts GaugeOpts) Gauge {
-	desc := NewDesc(
-		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
-		opts.Help,
-		nil,
-		opts.ConstLabels,
-	)
-	result := &gauge{desc: desc, labelPairs: desc.constLabelPairs}
-	result.init(result) // Init self-collection.
-	return result
-}
-
-type gauge struct {
-	// valBits contains the bits of the represented float64 value. It has
-	// to go first in the struct to guarantee alignment for atomic
-	// operations.  http://golang.org/pkg/sync/atomic/#pkg-note-BUG
-	valBits uint64
-
-	selfCollector
-
-	desc       *Desc
-	labelPairs []*dto.LabelPair
-}
-
-func (g *gauge) Desc() *Desc {
-	return g.desc
-}
-
-func (g *gauge) Set(val float64) {
-	atomic.StoreUint64(&g.valBits, math.Float64bits(val))
-}
-
-func (g *gauge) SetToCurrentTime() {
-	g.Set(float64(time.Now().UnixNano()) / 1e9)
-}
-
-func (g *gauge) Inc() {
-	g.Add(1)
-}
-
-func (g *gauge) Dec() {
-	g.Add(-1)
-}
-
-func (g *gauge) Add(val float64) {
-	for {
-		oldBits := atomic.LoadUint64(&g.valBits)
-		newBits := math.Float64bits(math.Float64frombits(oldBits) + val)
-		if atomic.CompareAndSwapUint64(&g.valBits, oldBits, newBits) {
-			return
-		}
-	}
-}
-
-func (g *gauge) Sub(val float64) {
-	g.Add(val * -1)
-}
-
-func (g *gauge) Write(out *dto.Metric) error {
-	val := math.Float64frombits(atomic.LoadUint64(&g.valBits))
-	return populateMetric(GaugeValue, val, g.labelPairs, out)
-}
-
-// GaugeVec is a Collector that bundles a set of Gauges that all share the same
-// Desc, but have different values for their variable labels. This is used if
-// you want to count the same thing partitioned by various dimensions
-// (e.g. number of operations queued, partitioned by user and operation
-// type). Create instances with NewGaugeVec.
-type GaugeVec struct {
-	*metricVec
-}
-
-// NewGaugeVec creates a new GaugeVec based on the provided GaugeOpts and
-// partitioned by the given label names.
-func NewGaugeVec(opts GaugeOpts, labelNames []string) *GaugeVec {
-	desc := NewDesc(
-		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
-		opts.Help,
-		labelNames,
-		opts.ConstLabels,
-	)
-	return &GaugeVec{
-		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
-			if len(lvs) != len(desc.variableLabels) {
-				panic(errInconsistentCardinality)
-			}
-			result := &gauge{desc: desc, labelPairs: makeLabelPairs(desc, lvs)}
-			result.init(result) // Init self-collection.
-			return result
-		}),
-	}
-}
-
-// GetMetricWithLabelValues returns the Gauge for the given slice of label
-// values (same order as the VariableLabels in Desc). If that combination of
-// label values is accessed for the first time, a new Gauge is created.
-//
-// It is possible to call this method without using the returned Gauge to only
-// create the new Gauge but leave it at its starting value 0. See also the
-// SummaryVec example.
-//
-// Keeping the Gauge for later use is possible (and should be considered if
-// performance is critical), but keep in mind that Reset, DeleteLabelValues and
-// Delete can be used to delete the Gauge from the GaugeVec. In that case, the
-// Gauge will still exist, but it will not be exported anymore, even if a
-// Gauge with the same label values is created later. See also the CounterVec
-// example.
-//
-// An error is returned if the number of label values is not the same as the
-// number of VariableLabels in Desc (minus any curried labels).
-//
-// Note that for more than one label value, this method is prone to mistakes
-// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
-// an alternative to avoid that type of mistake. For higher label numbers, the
-// latter has a much more readable (albeit more verbose) syntax, but it comes
-// with a performance overhead (for creating and processing the Labels map).
-func (v *GaugeVec) GetMetricWithLabelValues(lvs ...string) (Gauge, error) {
-	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
-	if metric != nil {
-		return metric.(Gauge), err
-	}
-	return nil, err
-}
-
-// GetMetricWith returns the Gauge for the given Labels map (the label names
-// must match those of the VariableLabels in Desc). If that label map is
-// accessed for the first time, a new Gauge is created. Implications of
-// creating a Gauge without using it and keeping the Gauge for later use are
-// the same as for GetMetricWithLabelValues.
-//
-// An error is returned if the number and names of the Labels are inconsistent
-// with those of the VariableLabels in Desc (minus any curried labels).
-//
-// This method is used for the same purpose as
-// GetMetricWithLabelValues(...string). See there for pros and cons of the two
-// methods.
-func (v *GaugeVec) GetMetricWith(labels Labels) (Gauge, error) {
-	metric, err := v.metricVec.getMetricWith(labels)
-	if metric != nil {
-		return metric.(Gauge), err
-	}
-	return nil, err
-}
-
-// WithLabelValues works as GetMetricWithLabelValues, but panics where
-// GetMetricWithLabelValues would have returned an error. Not returning an
-// error allows shortcuts like
-//     myVec.WithLabelValues("404", "GET").Add(42)
-func (v *GaugeVec) WithLabelValues(lvs ...string) Gauge {
-	g, err := v.GetMetricWithLabelValues(lvs...)
-	if err != nil {
-		panic(err)
-	}
-	return g
-}
-
-// With works as GetMetricWith, but panics where GetMetricWithLabels would have
-// returned an error. Not returning an error allows shortcuts like
-//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Add(42)
-func (v *GaugeVec) With(labels Labels) Gauge {
-	g, err := v.GetMetricWith(labels)
-	if err != nil {
-		panic(err)
-	}
-	return g
-}
-
-// CurryWith returns a vector curried with the provided labels, i.e. the
-// returned vector has those labels pre-set for all labeled operations performed
-// on it. The cardinality of the curried vector is reduced accordingly. The
-// order of the remaining labels stays the same (just with the curried labels
-// taken out of the sequence – which is relevant for the
-// (GetMetric)WithLabelValues methods). It is possible to curry a curried
-// vector, but only with labels not yet used for currying before.
-//
-// The metrics contained in the GaugeVec are shared between the curried and
-// uncurried vectors. They are just accessed differently. Curried and uncurried
-// vectors behave identically in terms of collection. Only one must be
-// registered with a given registry (usually the uncurried version). The Reset
-// method deletes all metrics, even if called on a curried vector.
-func (v *GaugeVec) CurryWith(labels Labels) (*GaugeVec, error) {
-	vec, err := v.curryWith(labels)
-	if vec != nil {
-		return &GaugeVec{vec}, err
-	}
-	return nil, err
-}
-
-// MustCurryWith works as CurryWith but panics where CurryWith would have
-// returned an error.
-func (v *GaugeVec) MustCurryWith(labels Labels) *GaugeVec {
-	vec, err := v.CurryWith(labels)
-	if err != nil {
-		panic(err)
-	}
-	return vec
-}
-
-// GaugeFunc is a Gauge whose value is determined at collect time by calling a
-// provided function.
-//
-// To create GaugeFunc instances, use NewGaugeFunc.
-type GaugeFunc interface {
-	Metric
-	Collector
-}
-
-// NewGaugeFunc creates a new GaugeFunc based on the provided GaugeOpts. The
-// value reported is determined by calling the given function from within the
-// Write method. Take into account that metric collection may happen
-// concurrently. If that results in concurrent calls to Write, like in the case
-// where a GaugeFunc is directly registered with Prometheus, the provided
-// function must be concurrency-safe.
-func NewGaugeFunc(opts GaugeOpts, function func() float64) GaugeFunc {
-	return newValueFunc(NewDesc(
-		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
-		opts.Help,
-		nil,
-		opts.ConstLabels,
-	), GaugeValue, function)
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go b/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go
deleted file mode 100644
index ba3b933..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/go_collector.go
+++ /dev/null
@@ -1,301 +0,0 @@
-// Copyright 2018 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"fmt"
-	"runtime"
-	"runtime/debug"
-	"time"
-)
-
-type goCollector struct {
-	goroutinesDesc *Desc
-	threadsDesc    *Desc
-	gcDesc         *Desc
-	goInfoDesc     *Desc
-
-	// metrics to describe and collect
-	metrics memStatsMetrics
-}
-
-// NewGoCollector returns a collector which exports metrics about the current Go
-// process. This includes memory stats. To collect those, runtime.ReadMemStats
-// is called. This causes a stop-the-world, which is very short with Go1.9+
-// (~25µs). However, with older Go versions, the stop-the-world duration depends
-// on the heap size and can be quite significant (~1.7 ms/GiB as per
-// https://go-review.googlesource.com/c/go/+/34937).
-func NewGoCollector() Collector {
-	return &goCollector{
-		goroutinesDesc: NewDesc(
-			"go_goroutines",
-			"Number of goroutines that currently exist.",
-			nil, nil),
-		threadsDesc: NewDesc(
-			"go_threads",
-			"Number of OS threads created.",
-			nil, nil),
-		gcDesc: NewDesc(
-			"go_gc_duration_seconds",
-			"A summary of the GC invocation durations.",
-			nil, nil),
-		goInfoDesc: NewDesc(
-			"go_info",
-			"Information about the Go environment.",
-			nil, Labels{"version": runtime.Version()}),
-		metrics: memStatsMetrics{
-			{
-				desc: NewDesc(
-					memstatNamespace("alloc_bytes"),
-					"Number of bytes allocated and still in use.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Alloc) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("alloc_bytes_total"),
-					"Total number of bytes allocated, even if freed.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.TotalAlloc) },
-				valType: CounterValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("sys_bytes"),
-					"Number of bytes obtained from system.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Sys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("lookups_total"),
-					"Total number of pointer lookups.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Lookups) },
-				valType: CounterValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("mallocs_total"),
-					"Total number of mallocs.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Mallocs) },
-				valType: CounterValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("frees_total"),
-					"Total number of frees.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.Frees) },
-				valType: CounterValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("heap_alloc_bytes"),
-					"Number of heap bytes allocated and still in use.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapAlloc) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("heap_sys_bytes"),
-					"Number of heap bytes obtained from system.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("heap_idle_bytes"),
-					"Number of heap bytes waiting to be used.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapIdle) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("heap_inuse_bytes"),
-					"Number of heap bytes that are in use.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapInuse) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("heap_released_bytes"),
-					"Number of heap bytes released to OS.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapReleased) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("heap_objects"),
-					"Number of allocated objects.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.HeapObjects) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("stack_inuse_bytes"),
-					"Number of bytes in use by the stack allocator.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.StackInuse) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("stack_sys_bytes"),
-					"Number of bytes obtained from system for stack allocator.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.StackSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("mspan_inuse_bytes"),
-					"Number of bytes in use by mspan structures.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MSpanInuse) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("mspan_sys_bytes"),
-					"Number of bytes used for mspan structures obtained from system.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MSpanSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("mcache_inuse_bytes"),
-					"Number of bytes in use by mcache structures.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MCacheInuse) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("mcache_sys_bytes"),
-					"Number of bytes used for mcache structures obtained from system.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.MCacheSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("buck_hash_sys_bytes"),
-					"Number of bytes used by the profiling bucket hash table.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.BuckHashSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("gc_sys_bytes"),
-					"Number of bytes used for garbage collection system metadata.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.GCSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("other_sys_bytes"),
-					"Number of bytes used for other system allocations.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.OtherSys) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("next_gc_bytes"),
-					"Number of heap bytes when next garbage collection will take place.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.NextGC) },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("last_gc_time_seconds"),
-					"Number of seconds since 1970 of last garbage collection.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return float64(ms.LastGC) / 1e9 },
-				valType: GaugeValue,
-			}, {
-				desc: NewDesc(
-					memstatNamespace("gc_cpu_fraction"),
-					"The fraction of this program's available CPU time used by the GC since the program started.",
-					nil, nil,
-				),
-				eval:    func(ms *runtime.MemStats) float64 { return ms.GCCPUFraction },
-				valType: GaugeValue,
-			},
-		},
-	}
-}
-
-func memstatNamespace(s string) string {
-	return fmt.Sprintf("go_memstats_%s", s)
-}
-
-// Describe returns all descriptions of the collector.
-func (c *goCollector) Describe(ch chan<- *Desc) {
-	ch <- c.goroutinesDesc
-	ch <- c.threadsDesc
-	ch <- c.gcDesc
-	ch <- c.goInfoDesc
-	for _, i := range c.metrics {
-		ch <- i.desc
-	}
-}
-
-// Collect returns the current state of all metrics of the collector.
-func (c *goCollector) Collect(ch chan<- Metric) {
-	ch <- MustNewConstMetric(c.goroutinesDesc, GaugeValue, float64(runtime.NumGoroutine()))
-	n, _ := runtime.ThreadCreateProfile(nil)
-	ch <- MustNewConstMetric(c.threadsDesc, GaugeValue, float64(n))
-
-	var stats debug.GCStats
-	stats.PauseQuantiles = make([]time.Duration, 5)
-	debug.ReadGCStats(&stats)
-
-	quantiles := make(map[float64]float64)
-	for idx, pq := range stats.PauseQuantiles[1:] {
-		quantiles[float64(idx+1)/float64(len(stats.PauseQuantiles)-1)] = pq.Seconds()
-	}
-	quantiles[0.0] = stats.PauseQuantiles[0].Seconds()
-	ch <- MustNewConstSummary(c.gcDesc, uint64(stats.NumGC), stats.PauseTotal.Seconds(), quantiles)
-
-	ch <- MustNewConstMetric(c.goInfoDesc, GaugeValue, 1)
-
-	ms := &runtime.MemStats{}
-	runtime.ReadMemStats(ms)
-	for _, i := range c.metrics {
-		ch <- MustNewConstMetric(i.desc, i.valType, i.eval(ms))
-	}
-}
-
-// memStatsMetrics provide description, value, and value type for memstat metrics.
-type memStatsMetrics []struct {
-	desc    *Desc
-	eval    func(*runtime.MemStats) float64
-	valType ValueType
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/histogram.go b/vendor/github.com/prometheus/client_golang/prometheus/histogram.go
deleted file mode 100644
index 331783a..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/histogram.go
+++ /dev/null
@@ -1,505 +0,0 @@
-// Copyright 2015 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"fmt"
-	"math"
-	"sort"
-	"sync/atomic"
-
-	"github.com/golang/protobuf/proto"
-
-	dto "github.com/prometheus/client_model/go"
-)
-
-// A Histogram counts individual observations from an event or sample stream in
-// configurable buckets. Similar to a summary, it also provides a sum of
-// observations and an observation count.
-//
-// On the Prometheus server, quantiles can be calculated from a Histogram using
-// the histogram_quantile function in the query language.
-//
-// Note that Histograms, in contrast to Summaries, can be aggregated with the
-// Prometheus query language (see the documentation for detailed
-// procedures). However, Histograms require the user to pre-define suitable
-// buckets, and they are in general less accurate. The Observe method of a
-// Histogram has a very low performance overhead in comparison with the Observe
-// method of a Summary.
-//
-// To create Histogram instances, use NewHistogram.
-type Histogram interface {
-	Metric
-	Collector
-
-	// Observe adds a single observation to the histogram.
-	Observe(float64)
-}
-
-// bucketLabel is used for the label that defines the upper bound of a
-// bucket of a histogram ("le" -> "less or equal").
-const bucketLabel = "le"
-
-// DefBuckets are the default Histogram buckets. The default buckets are
-// tailored to broadly measure the response time (in seconds) of a network
-// service. Most likely, however, you will be required to define buckets
-// customized to your use case.
-var (
-	DefBuckets = []float64{.005, .01, .025, .05, .1, .25, .5, 1, 2.5, 5, 10}
-
-	errBucketLabelNotAllowed = fmt.Errorf(
-		"%q is not allowed as label name in histograms", bucketLabel,
-	)
-)
-
-// LinearBuckets creates 'count' buckets, each 'width' wide, where the lowest
-// bucket has an upper bound of 'start'. The final +Inf bucket is not counted
-// and not included in the returned slice. The returned slice is meant to be
-// used for the Buckets field of HistogramOpts.
-//
-// The function panics if 'count' is zero or negative.
-func LinearBuckets(start, width float64, count int) []float64 {
-	if count < 1 {
-		panic("LinearBuckets needs a positive count")
-	}
-	buckets := make([]float64, count)
-	for i := range buckets {
-		buckets[i] = start
-		start += width
-	}
-	return buckets
-}
-
-// ExponentialBuckets creates 'count' buckets, where the lowest bucket has an
-// upper bound of 'start' and each following bucket's upper bound is 'factor'
-// times the previous bucket's upper bound. The final +Inf bucket is not counted
-// and not included in the returned slice. The returned slice is meant to be
-// used for the Buckets field of HistogramOpts.
-//
-// The function panics if 'count' is 0 or negative, if 'start' is 0 or negative,
-// or if 'factor' is less than or equal 1.
-func ExponentialBuckets(start, factor float64, count int) []float64 {
-	if count < 1 {
-		panic("ExponentialBuckets needs a positive count")
-	}
-	if start <= 0 {
-		panic("ExponentialBuckets needs a positive start value")
-	}
-	if factor <= 1 {
-		panic("ExponentialBuckets needs a factor greater than 1")
-	}
-	buckets := make([]float64, count)
-	for i := range buckets {
-		buckets[i] = start
-		start *= factor
-	}
-	return buckets
-}
-
-// HistogramOpts bundles the options for creating a Histogram metric. It is
-// mandatory to set Name and Help to a non-empty string. All other fields are
-// optional and can safely be left at their zero value.
-type HistogramOpts struct {
-	// Namespace, Subsystem, and Name are components of the fully-qualified
-	// name of the Histogram (created by joining these components with
-	// "_"). Only Name is mandatory, the others merely help structuring the
-	// name. Note that the fully-qualified name of the Histogram must be a
-	// valid Prometheus metric name.
-	Namespace string
-	Subsystem string
-	Name      string
-
-	// Help provides information about this Histogram. Mandatory!
-	//
-	// Metrics with the same fully-qualified name must have the same Help
-	// string.
-	Help string
-
-	// ConstLabels are used to attach fixed labels to this metric. Metrics
-	// with the same fully-qualified name must have the same label names in
-	// their ConstLabels.
-	//
-	// ConstLabels are only used rarely. In particular, do not use them to
-	// attach the same labels to all your metrics. Those use cases are
-	// better covered by target labels set by the scraping Prometheus
-	// server, or by one specific metric (e.g. a build_info or a
-	// machine_role metric). See also
-	// https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels
-	ConstLabels Labels
-
-	// Buckets defines the buckets into which observations are counted. Each
-	// element in the slice is the upper inclusive bound of a bucket. The
-	// values must be sorted in strictly increasing order. There is no need
-	// to add a highest bucket with +Inf bound, it will be added
-	// implicitly. The default value is DefBuckets.
-	Buckets []float64
-}
-
-// NewHistogram creates a new Histogram based on the provided HistogramOpts. It
-// panics if the buckets in HistogramOpts are not in strictly increasing order.
-func NewHistogram(opts HistogramOpts) Histogram {
-	return newHistogram(
-		NewDesc(
-			BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
-			opts.Help,
-			nil,
-			opts.ConstLabels,
-		),
-		opts,
-	)
-}
-
-func newHistogram(desc *Desc, opts HistogramOpts, labelValues ...string) Histogram {
-	if len(desc.variableLabels) != len(labelValues) {
-		panic(errInconsistentCardinality)
-	}
-
-	for _, n := range desc.variableLabels {
-		if n == bucketLabel {
-			panic(errBucketLabelNotAllowed)
-		}
-	}
-	for _, lp := range desc.constLabelPairs {
-		if lp.GetName() == bucketLabel {
-			panic(errBucketLabelNotAllowed)
-		}
-	}
-
-	if len(opts.Buckets) == 0 {
-		opts.Buckets = DefBuckets
-	}
-
-	h := &histogram{
-		desc:        desc,
-		upperBounds: opts.Buckets,
-		labelPairs:  makeLabelPairs(desc, labelValues),
-	}
-	for i, upperBound := range h.upperBounds {
-		if i < len(h.upperBounds)-1 {
-			if upperBound >= h.upperBounds[i+1] {
-				panic(fmt.Errorf(
-					"histogram buckets must be in increasing order: %f >= %f",
-					upperBound, h.upperBounds[i+1],
-				))
-			}
-		} else {
-			if math.IsInf(upperBound, +1) {
-				// The +Inf bucket is implicit. Remove it here.
-				h.upperBounds = h.upperBounds[:i]
-			}
-		}
-	}
-	// Finally we know the final length of h.upperBounds and can make counts.
-	h.counts = make([]uint64, len(h.upperBounds))
-
-	h.init(h) // Init self-collection.
-	return h
-}
-
-type histogram struct {
-	// sumBits contains the bits of the float64 representing the sum of all
-	// observations. sumBits and count have to go first in the struct to
-	// guarantee alignment for atomic operations.
-	// http://golang.org/pkg/sync/atomic/#pkg-note-BUG
-	sumBits uint64
-	count   uint64
-
-	selfCollector
-	// Note that there is no mutex required.
-
-	desc *Desc
-
-	upperBounds []float64
-	counts      []uint64
-
-	labelPairs []*dto.LabelPair
-}
-
-func (h *histogram) Desc() *Desc {
-	return h.desc
-}
-
-func (h *histogram) Observe(v float64) {
-	// TODO(beorn7): For small numbers of buckets (<30), a linear search is
-	// slightly faster than the binary search. If we really care, we could
-	// switch from one search strategy to the other depending on the number
-	// of buckets.
-	//
-	// Microbenchmarks (BenchmarkHistogramNoLabels):
-	// 11 buckets: 38.3 ns/op linear - binary 48.7 ns/op
-	// 100 buckets: 78.1 ns/op linear - binary 54.9 ns/op
-	// 300 buckets: 154 ns/op linear - binary 61.6 ns/op
-	i := sort.SearchFloat64s(h.upperBounds, v)
-	if i < len(h.counts) {
-		atomic.AddUint64(&h.counts[i], 1)
-	}
-	atomic.AddUint64(&h.count, 1)
-	for {
-		oldBits := atomic.LoadUint64(&h.sumBits)
-		newBits := math.Float64bits(math.Float64frombits(oldBits) + v)
-		if atomic.CompareAndSwapUint64(&h.sumBits, oldBits, newBits) {
-			break
-		}
-	}
-}
-
-func (h *histogram) Write(out *dto.Metric) error {
-	his := &dto.Histogram{}
-	buckets := make([]*dto.Bucket, len(h.upperBounds))
-
-	his.SampleSum = proto.Float64(math.Float64frombits(atomic.LoadUint64(&h.sumBits)))
-	his.SampleCount = proto.Uint64(atomic.LoadUint64(&h.count))
-	var count uint64
-	for i, upperBound := range h.upperBounds {
-		count += atomic.LoadUint64(&h.counts[i])
-		buckets[i] = &dto.Bucket{
-			CumulativeCount: proto.Uint64(count),
-			UpperBound:      proto.Float64(upperBound),
-		}
-	}
-	his.Bucket = buckets
-	out.Histogram = his
-	out.Label = h.labelPairs
-	return nil
-}
-
-// HistogramVec is a Collector that bundles a set of Histograms that all share the
-// same Desc, but have different values for their variable labels. This is used
-// if you want to count the same thing partitioned by various dimensions
-// (e.g. HTTP request latencies, partitioned by status code and method). Create
-// instances with NewHistogramVec.
-type HistogramVec struct {
-	*metricVec
-}
-
-// NewHistogramVec creates a new HistogramVec based on the provided HistogramOpts and
-// partitioned by the given label names.
-func NewHistogramVec(opts HistogramOpts, labelNames []string) *HistogramVec {
-	desc := NewDesc(
-		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
-		opts.Help,
-		labelNames,
-		opts.ConstLabels,
-	)
-	return &HistogramVec{
-		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
-			return newHistogram(desc, opts, lvs...)
-		}),
-	}
-}
-
-// GetMetricWithLabelValues returns the Histogram for the given slice of label
-// values (same order as the VariableLabels in Desc). If that combination of
-// label values is accessed for the first time, a new Histogram is created.
-//
-// It is possible to call this method without using the returned Histogram to only
-// create the new Histogram but leave it at its starting value, a Histogram without
-// any observations.
-//
-// Keeping the Histogram for later use is possible (and should be considered if
-// performance is critical), but keep in mind that Reset, DeleteLabelValues and
-// Delete can be used to delete the Histogram from the HistogramVec. In that case, the
-// Histogram will still exist, but it will not be exported anymore, even if a
-// Histogram with the same label values is created later. See also the CounterVec
-// example.
-//
-// An error is returned if the number of label values is not the same as the
-// number of VariableLabels in Desc (minus any curried labels).
-//
-// Note that for more than one label value, this method is prone to mistakes
-// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
-// an alternative to avoid that type of mistake. For higher label numbers, the
-// latter has a much more readable (albeit more verbose) syntax, but it comes
-// with a performance overhead (for creating and processing the Labels map).
-// See also the GaugeVec example.
-func (v *HistogramVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) {
-	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
-	if metric != nil {
-		return metric.(Observer), err
-	}
-	return nil, err
-}
-
-// GetMetricWith returns the Histogram for the given Labels map (the label names
-// must match those of the VariableLabels in Desc). If that label map is
-// accessed for the first time, a new Histogram is created. Implications of
-// creating a Histogram without using it and keeping the Histogram for later use
-// are the same as for GetMetricWithLabelValues.
-//
-// An error is returned if the number and names of the Labels are inconsistent
-// with those of the VariableLabels in Desc (minus any curried labels).
-//
-// This method is used for the same purpose as
-// GetMetricWithLabelValues(...string). See there for pros and cons of the two
-// methods.
-func (v *HistogramVec) GetMetricWith(labels Labels) (Observer, error) {
-	metric, err := v.metricVec.getMetricWith(labels)
-	if metric != nil {
-		return metric.(Observer), err
-	}
-	return nil, err
-}
-
-// WithLabelValues works as GetMetricWithLabelValues, but panics where
-// GetMetricWithLabelValues would have returned an error. Not returning an
-// error allows shortcuts like
-//     myVec.WithLabelValues("404", "GET").Observe(42.21)
-func (v *HistogramVec) WithLabelValues(lvs ...string) Observer {
-	h, err := v.GetMetricWithLabelValues(lvs...)
-	if err != nil {
-		panic(err)
-	}
-	return h
-}
-
-// With works as GetMetricWith but panics where GetMetricWithLabels would have
-// returned an error. Not returning an error allows shortcuts like
-//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Observe(42.21)
-func (v *HistogramVec) With(labels Labels) Observer {
-	h, err := v.GetMetricWith(labels)
-	if err != nil {
-		panic(err)
-	}
-	return h
-}
-
-// CurryWith returns a vector curried with the provided labels, i.e. the
-// returned vector has those labels pre-set for all labeled operations performed
-// on it. The cardinality of the curried vector is reduced accordingly. The
-// order of the remaining labels stays the same (just with the curried labels
-// taken out of the sequence – which is relevant for the
-// (GetMetric)WithLabelValues methods). It is possible to curry a curried
-// vector, but only with labels not yet used for currying before.
-//
-// The metrics contained in the HistogramVec are shared between the curried and
-// uncurried vectors. They are just accessed differently. Curried and uncurried
-// vectors behave identically in terms of collection. Only one must be
-// registered with a given registry (usually the uncurried version). The Reset
-// method deletes all metrics, even if called on a curried vector.
-func (v *HistogramVec) CurryWith(labels Labels) (ObserverVec, error) {
-	vec, err := v.curryWith(labels)
-	if vec != nil {
-		return &HistogramVec{vec}, err
-	}
-	return nil, err
-}
-
-// MustCurryWith works as CurryWith but panics where CurryWith would have
-// returned an error.
-func (v *HistogramVec) MustCurryWith(labels Labels) ObserverVec {
-	vec, err := v.CurryWith(labels)
-	if err != nil {
-		panic(err)
-	}
-	return vec
-}
-
-type constHistogram struct {
-	desc       *Desc
-	count      uint64
-	sum        float64
-	buckets    map[float64]uint64
-	labelPairs []*dto.LabelPair
-}
-
-func (h *constHistogram) Desc() *Desc {
-	return h.desc
-}
-
-func (h *constHistogram) Write(out *dto.Metric) error {
-	his := &dto.Histogram{}
-	buckets := make([]*dto.Bucket, 0, len(h.buckets))
-
-	his.SampleCount = proto.Uint64(h.count)
-	his.SampleSum = proto.Float64(h.sum)
-
-	for upperBound, count := range h.buckets {
-		buckets = append(buckets, &dto.Bucket{
-			CumulativeCount: proto.Uint64(count),
-			UpperBound:      proto.Float64(upperBound),
-		})
-	}
-
-	if len(buckets) > 0 {
-		sort.Sort(buckSort(buckets))
-	}
-	his.Bucket = buckets
-
-	out.Histogram = his
-	out.Label = h.labelPairs
-
-	return nil
-}
-
-// NewConstHistogram returns a metric representing a Prometheus histogram with
-// fixed values for the count, sum, and bucket counts. As those parameters
-// cannot be changed, the returned value does not implement the Histogram
-// interface (but only the Metric interface). Users of this package will not
-// have much use for it in regular operations. However, when implementing custom
-// Collectors, it is useful as a throw-away metric that is generated on the fly
-// to send it to Prometheus in the Collect method.
-//
-// buckets is a map of upper bounds to cumulative counts, excluding the +Inf
-// bucket.
-//
-// NewConstHistogram returns an error if the length of labelValues is not
-// consistent with the variable labels in Desc.
-func NewConstHistogram(
-	desc *Desc,
-	count uint64,
-	sum float64,
-	buckets map[float64]uint64,
-	labelValues ...string,
-) (Metric, error) {
-	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
-		return nil, err
-	}
-	return &constHistogram{
-		desc:       desc,
-		count:      count,
-		sum:        sum,
-		buckets:    buckets,
-		labelPairs: makeLabelPairs(desc, labelValues),
-	}, nil
-}
-
-// MustNewConstHistogram is a version of NewConstHistogram that panics where
-// NewConstMetric would have returned an error.
-func MustNewConstHistogram(
-	desc *Desc,
-	count uint64,
-	sum float64,
-	buckets map[float64]uint64,
-	labelValues ...string,
-) Metric {
-	m, err := NewConstHistogram(desc, count, sum, buckets, labelValues...)
-	if err != nil {
-		panic(err)
-	}
-	return m
-}
-
-type buckSort []*dto.Bucket
-
-func (s buckSort) Len() int {
-	return len(s)
-}
-
-func (s buckSort) Swap(i, j int) {
-	s[i], s[j] = s[j], s[i]
-}
-
-func (s buckSort) Less(i, j int) bool {
-	return s[i].GetUpperBound() < s[j].GetUpperBound()
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/http.go b/vendor/github.com/prometheus/client_golang/prometheus/http.go
deleted file mode 100644
index 3f1fa15..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/http.go
+++ /dev/null
@@ -1,512 +0,0 @@
-// Copyright 2014 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"bufio"
-	"bytes"
-	"compress/gzip"
-	"fmt"
-	"io"
-	"net"
-	"net/http"
-	"strconv"
-	"strings"
-	"sync"
-	"time"
-
-	"github.com/prometheus/common/expfmt"
-)
-
-// TODO(beorn7): Remove this whole file. It is a partial mirror of
-// promhttp/http.go (to avoid circular import chains) where everything HTTP
-// related should live. The functions here are just for avoiding
-// breakage. Everything is deprecated.
-
-const (
-	contentTypeHeader     = "Content-Type"
-	contentLengthHeader   = "Content-Length"
-	contentEncodingHeader = "Content-Encoding"
-	acceptEncodingHeader  = "Accept-Encoding"
-)
-
-var bufPool sync.Pool
-
-func getBuf() *bytes.Buffer {
-	buf := bufPool.Get()
-	if buf == nil {
-		return &bytes.Buffer{}
-	}
-	return buf.(*bytes.Buffer)
-}
-
-func giveBuf(buf *bytes.Buffer) {
-	buf.Reset()
-	bufPool.Put(buf)
-}
-
-// Handler returns an HTTP handler for the DefaultGatherer. It is
-// already instrumented with InstrumentHandler (using "prometheus" as handler
-// name).
-//
-// Deprecated: Please note the issues described in the doc comment of
-// InstrumentHandler. You might want to consider using
-// promhttp.InstrumentedHandler instead.
-func Handler() http.Handler {
-	return InstrumentHandler("prometheus", UninstrumentedHandler())
-}
-
-// UninstrumentedHandler returns an HTTP handler for the DefaultGatherer.
-//
-// Deprecated: Use promhttp.Handler instead. See there for further documentation.
-func UninstrumentedHandler() http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
-		mfs, err := DefaultGatherer.Gather()
-		if err != nil {
-			http.Error(w, "An error has occurred during metrics collection:\n\n"+err.Error(), http.StatusInternalServerError)
-			return
-		}
-
-		contentType := expfmt.Negotiate(req.Header)
-		buf := getBuf()
-		defer giveBuf(buf)
-		writer, encoding := decorateWriter(req, buf)
-		enc := expfmt.NewEncoder(writer, contentType)
-		var lastErr error
-		for _, mf := range mfs {
-			if err := enc.Encode(mf); err != nil {
-				lastErr = err
-				http.Error(w, "An error has occurred during metrics encoding:\n\n"+err.Error(), http.StatusInternalServerError)
-				return
-			}
-		}
-		if closer, ok := writer.(io.Closer); ok {
-			closer.Close()
-		}
-		if lastErr != nil && buf.Len() == 0 {
-			http.Error(w, "No metrics encoded, last error:\n\n"+lastErr.Error(), http.StatusInternalServerError)
-			return
-		}
-		header := w.Header()
-		header.Set(contentTypeHeader, string(contentType))
-		header.Set(contentLengthHeader, fmt.Sprint(buf.Len()))
-		if encoding != "" {
-			header.Set(contentEncodingHeader, encoding)
-		}
-		w.Write(buf.Bytes())
-	})
-}
-
-// decorateWriter wraps a writer to handle gzip compression if requested.  It
-// returns the decorated writer and the appropriate "Content-Encoding" header
-// (which is empty if no compression is enabled).
-func decorateWriter(request *http.Request, writer io.Writer) (io.Writer, string) {
-	header := request.Header.Get(acceptEncodingHeader)
-	parts := strings.Split(header, ",")
-	for _, part := range parts {
-		part = strings.TrimSpace(part)
-		if part == "gzip" || strings.HasPrefix(part, "gzip;") {
-			return gzip.NewWriter(writer), "gzip"
-		}
-	}
-	return writer, ""
-}
-
-var instLabels = []string{"method", "code"}
-
-type nower interface {
-	Now() time.Time
-}
-
-type nowFunc func() time.Time
-
-func (n nowFunc) Now() time.Time {
-	return n()
-}
-
-var now nower = nowFunc(func() time.Time {
-	return time.Now()
-})
-
-// InstrumentHandler wraps the given HTTP handler for instrumentation. It
-// registers four metric collectors (if not already done) and reports HTTP
-// metrics to the (newly or already) registered collectors: http_requests_total
-// (CounterVec), http_request_duration_microseconds (Summary),
-// http_request_size_bytes (Summary), http_response_size_bytes (Summary). Each
-// has a constant label named "handler" with the provided handlerName as
-// value. http_requests_total is a metric vector partitioned by HTTP method
-// (label name "method") and HTTP status code (label name "code").
-//
-// Deprecated: InstrumentHandler has several issues. Use the tooling provided in
-// package promhttp instead. The issues are the following:
-//
-// - It uses Summaries rather than Histograms. Summaries are not useful if
-// aggregation across multiple instances is required.
-//
-// - It uses microseconds as unit, which is deprecated and should be replaced by
-// seconds.
-//
-// - The size of the request is calculated in a separate goroutine. Since this
-// calculator requires access to the request header, it creates a race with
-// any writes to the header performed during request handling.
-// httputil.ReverseProxy is a prominent example for a handler
-// performing such writes.
-//
-// - It has additional issues with HTTP/2, cf.
-// https://github.com/prometheus/client_golang/issues/272.
-func InstrumentHandler(handlerName string, handler http.Handler) http.HandlerFunc {
-	return InstrumentHandlerFunc(handlerName, handler.ServeHTTP)
-}
-
-// InstrumentHandlerFunc wraps the given function for instrumentation. It
-// otherwise works in the same way as InstrumentHandler (and shares the same
-// issues).
-//
-// Deprecated: InstrumentHandlerFunc is deprecated for the same reasons as
-// InstrumentHandler is. Use the tooling provided in package promhttp instead.
-func InstrumentHandlerFunc(handlerName string, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
-	return InstrumentHandlerFuncWithOpts(
-		SummaryOpts{
-			Subsystem:   "http",
-			ConstLabels: Labels{"handler": handlerName},
-			Objectives:  map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001},
-		},
-		handlerFunc,
-	)
-}
-
-// InstrumentHandlerWithOpts works like InstrumentHandler (and shares the same
-// issues) but provides more flexibility (at the cost of a more complex call
-// syntax). As InstrumentHandler, this function registers four metric
-// collectors, but it uses the provided SummaryOpts to create them. However, the
-// fields "Name" and "Help" in the SummaryOpts are ignored. "Name" is replaced
-// by "requests_total", "request_duration_microseconds", "request_size_bytes",
-// and "response_size_bytes", respectively. "Help" is replaced by an appropriate
-// help string. The names of the variable labels of the http_requests_total
-// CounterVec are "method" (get, post, etc.), and "code" (HTTP status code).
-//
-// If InstrumentHandlerWithOpts is called as follows, it mimics exactly the
-// behavior of InstrumentHandler:
-//
-//     prometheus.InstrumentHandlerWithOpts(
-//         prometheus.SummaryOpts{
-//              Subsystem:   "http",
-//              ConstLabels: prometheus.Labels{"handler": handlerName},
-//         },
-//         handler,
-//     )
-//
-// Technical detail: "requests_total" is a CounterVec, not a SummaryVec, so it
-// cannot use SummaryOpts. Instead, a CounterOpts struct is created internally,
-// and all its fields are set to the equally named fields in the provided
-// SummaryOpts.
-//
-// Deprecated: InstrumentHandlerWithOpts is deprecated for the same reasons as
-// InstrumentHandler is. Use the tooling provided in package promhttp instead.
-func InstrumentHandlerWithOpts(opts SummaryOpts, handler http.Handler) http.HandlerFunc {
-	return InstrumentHandlerFuncWithOpts(opts, handler.ServeHTTP)
-}
-
-// InstrumentHandlerFuncWithOpts works like InstrumentHandlerFunc (and shares
-// the same issues) but provides more flexibility (at the cost of a more complex
-// call syntax). See InstrumentHandlerWithOpts for details how the provided
-// SummaryOpts are used.
-//
-// Deprecated: InstrumentHandlerFuncWithOpts is deprecated for the same reasons
-// as InstrumentHandler is. Use the tooling provided in package promhttp instead.
-func InstrumentHandlerFuncWithOpts(opts SummaryOpts, handlerFunc func(http.ResponseWriter, *http.Request)) http.HandlerFunc {
-	reqCnt := NewCounterVec(
-		CounterOpts{
-			Namespace:   opts.Namespace,
-			Subsystem:   opts.Subsystem,
-			Name:        "requests_total",
-			Help:        "Total number of HTTP requests made.",
-			ConstLabels: opts.ConstLabels,
-		},
-		instLabels,
-	)
-	if err := Register(reqCnt); err != nil {
-		if are, ok := err.(AlreadyRegisteredError); ok {
-			reqCnt = are.ExistingCollector.(*CounterVec)
-		} else {
-			panic(err)
-		}
-	}
-
-	opts.Name = "request_duration_microseconds"
-	opts.Help = "The HTTP request latencies in microseconds."
-	reqDur := NewSummary(opts)
-	if err := Register(reqDur); err != nil {
-		if are, ok := err.(AlreadyRegisteredError); ok {
-			reqDur = are.ExistingCollector.(Summary)
-		} else {
-			panic(err)
-		}
-	}
-
-	opts.Name = "request_size_bytes"
-	opts.Help = "The HTTP request sizes in bytes."
-	reqSz := NewSummary(opts)
-	if err := Register(reqSz); err != nil {
-		if are, ok := err.(AlreadyRegisteredError); ok {
-			reqSz = are.ExistingCollector.(Summary)
-		} else {
-			panic(err)
-		}
-	}
-
-	opts.Name = "response_size_bytes"
-	opts.Help = "The HTTP response sizes in bytes."
-	resSz := NewSummary(opts)
-	if err := Register(resSz); err != nil {
-		if are, ok := err.(AlreadyRegisteredError); ok {
-			resSz = are.ExistingCollector.(Summary)
-		} else {
-			panic(err)
-		}
-	}
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		now := time.Now()
-
-		delegate := &responseWriterDelegator{ResponseWriter: w}
-		out := computeApproximateRequestSize(r)
-
-		_, cn := w.(http.CloseNotifier)
-		_, fl := w.(http.Flusher)
-		_, hj := w.(http.Hijacker)
-		_, rf := w.(io.ReaderFrom)
-		var rw http.ResponseWriter
-		if cn && fl && hj && rf {
-			rw = &fancyResponseWriterDelegator{delegate}
-		} else {
-			rw = delegate
-		}
-		handlerFunc(rw, r)
-
-		elapsed := float64(time.Since(now)) / float64(time.Microsecond)
-
-		method := sanitizeMethod(r.Method)
-		code := sanitizeCode(delegate.status)
-		reqCnt.WithLabelValues(method, code).Inc()
-		reqDur.Observe(elapsed)
-		resSz.Observe(float64(delegate.written))
-		reqSz.Observe(float64(<-out))
-	})
-}
-
-func computeApproximateRequestSize(r *http.Request) <-chan int {
-	// Get URL length in current goroutine for avoiding a race condition.
-	// HandlerFunc that runs in parallel may modify the URL.
-	s := 0
-	if r.URL != nil {
-		s += len(r.URL.String())
-	}
-
-	out := make(chan int, 1)
-
-	go func() {
-		s += len(r.Method)
-		s += len(r.Proto)
-		for name, values := range r.Header {
-			s += len(name)
-			for _, value := range values {
-				s += len(value)
-			}
-		}
-		s += len(r.Host)
-
-		// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
-
-		if r.ContentLength != -1 {
-			s += int(r.ContentLength)
-		}
-		out <- s
-		close(out)
-	}()
-
-	return out
-}
-
-type responseWriterDelegator struct {
-	http.ResponseWriter
-
-	status      int
-	written     int64
-	wroteHeader bool
-}
-
-func (r *responseWriterDelegator) WriteHeader(code int) {
-	r.status = code
-	r.wroteHeader = true
-	r.ResponseWriter.WriteHeader(code)
-}
-
-func (r *responseWriterDelegator) Write(b []byte) (int, error) {
-	if !r.wroteHeader {
-		r.WriteHeader(http.StatusOK)
-	}
-	n, err := r.ResponseWriter.Write(b)
-	r.written += int64(n)
-	return n, err
-}
-
-type fancyResponseWriterDelegator struct {
-	*responseWriterDelegator
-}
-
-func (f *fancyResponseWriterDelegator) CloseNotify() <-chan bool {
-	return f.ResponseWriter.(http.CloseNotifier).CloseNotify()
-}
-
-func (f *fancyResponseWriterDelegator) Flush() {
-	f.ResponseWriter.(http.Flusher).Flush()
-}
-
-func (f *fancyResponseWriterDelegator) Hijack() (net.Conn, *bufio.ReadWriter, error) {
-	return f.ResponseWriter.(http.Hijacker).Hijack()
-}
-
-func (f *fancyResponseWriterDelegator) ReadFrom(r io.Reader) (int64, error) {
-	if !f.wroteHeader {
-		f.WriteHeader(http.StatusOK)
-	}
-	n, err := f.ResponseWriter.(io.ReaderFrom).ReadFrom(r)
-	f.written += n
-	return n, err
-}
-
-func sanitizeMethod(m string) string {
-	switch m {
-	case "GET", "get":
-		return "get"
-	case "PUT", "put":
-		return "put"
-	case "HEAD", "head":
-		return "head"
-	case "POST", "post":
-		return "post"
-	case "DELETE", "delete":
-		return "delete"
-	case "CONNECT", "connect":
-		return "connect"
-	case "OPTIONS", "options":
-		return "options"
-	case "NOTIFY", "notify":
-		return "notify"
-	default:
-		return strings.ToLower(m)
-	}
-}
-
-func sanitizeCode(s int) string {
-	switch s {
-	case 100:
-		return "100"
-	case 101:
-		return "101"
-
-	case 200:
-		return "200"
-	case 201:
-		return "201"
-	case 202:
-		return "202"
-	case 203:
-		return "203"
-	case 204:
-		return "204"
-	case 205:
-		return "205"
-	case 206:
-		return "206"
-
-	case 300:
-		return "300"
-	case 301:
-		return "301"
-	case 302:
-		return "302"
-	case 304:
-		return "304"
-	case 305:
-		return "305"
-	case 307:
-		return "307"
-
-	case 400:
-		return "400"
-	case 401:
-		return "401"
-	case 402:
-		return "402"
-	case 403:
-		return "403"
-	case 404:
-		return "404"
-	case 405:
-		return "405"
-	case 406:
-		return "406"
-	case 407:
-		return "407"
-	case 408:
-		return "408"
-	case 409:
-		return "409"
-	case 410:
-		return "410"
-	case 411:
-		return "411"
-	case 412:
-		return "412"
-	case 413:
-		return "413"
-	case 414:
-		return "414"
-	case 415:
-		return "415"
-	case 416:
-		return "416"
-	case 417:
-		return "417"
-	case 418:
-		return "418"
-
-	case 500:
-		return "500"
-	case 501:
-		return "501"
-	case 502:
-		return "502"
-	case 503:
-		return "503"
-	case 504:
-		return "504"
-	case 505:
-		return "505"
-
-	case 428:
-		return "428"
-	case 429:
-		return "429"
-	case 431:
-		return "431"
-	case 511:
-		return "511"
-
-	default:
-		return strconv.Itoa(s)
-	}
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/labels.go b/vendor/github.com/prometheus/client_golang/prometheus/labels.go
deleted file mode 100644
index e68f132..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/labels.go
+++ /dev/null
@@ -1,70 +0,0 @@
-// Copyright 2018 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"errors"
-	"fmt"
-	"strings"
-	"unicode/utf8"
-
-	"github.com/prometheus/common/model"
-)
-
-// Labels represents a collection of label name -> value mappings. This type is
-// commonly used with the With(Labels) and GetMetricWith(Labels) methods of
-// metric vector Collectors, e.g.:
-//     myVec.With(Labels{"code": "404", "method": "GET"}).Add(42)
-//
-// The other use-case is the specification of constant label pairs in Opts or to
-// create a Desc.
-type Labels map[string]string
-
-// reservedLabelPrefix is a prefix which is not legal in user-supplied
-// label names.
-const reservedLabelPrefix = "__"
-
-var errInconsistentCardinality = errors.New("inconsistent label cardinality")
-
-func validateValuesInLabels(labels Labels, expectedNumberOfValues int) error {
-	if len(labels) != expectedNumberOfValues {
-		return errInconsistentCardinality
-	}
-
-	for name, val := range labels {
-		if !utf8.ValidString(val) {
-			return fmt.Errorf("label %s: value %q is not valid UTF-8", name, val)
-		}
-	}
-
-	return nil
-}
-
-func validateLabelValues(vals []string, expectedNumberOfValues int) error {
-	if len(vals) != expectedNumberOfValues {
-		return errInconsistentCardinality
-	}
-
-	for _, val := range vals {
-		if !utf8.ValidString(val) {
-			return fmt.Errorf("label value %q is not valid UTF-8", val)
-		}
-	}
-
-	return nil
-}
-
-func checkLabelName(l string) bool {
-	return model.LabelName(l).IsValid() && !strings.HasPrefix(l, reservedLabelPrefix)
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/metric.go b/vendor/github.com/prometheus/client_golang/prometheus/metric.go
deleted file mode 100644
index 06897f2..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/metric.go
+++ /dev/null
@@ -1,175 +0,0 @@
-// Copyright 2014 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"strings"
-	"time"
-
-	"github.com/gogo/protobuf/proto"
-
-	dto "github.com/prometheus/client_model/go"
-)
-
-const separatorByte byte = 255
-
-// A Metric models a single sample value with its meta data being exported to
-// Prometheus. Implementations of Metric in this package are Gauge, Counter,
-// Histogram, Summary, and Untyped.
-type Metric interface {
-	// Desc returns the descriptor for the Metric. This method idempotently
-	// returns the same descriptor throughout the lifetime of the
-	// Metric. The returned descriptor is immutable by contract. A Metric
-	// unable to describe itself must return an invalid descriptor (created
-	// with NewInvalidDesc).
-	Desc() *Desc
-	// Write encodes the Metric into a "Metric" Protocol Buffer data
-	// transmission object.
-	//
-	// Metric implementations must observe concurrency safety as reads of
-	// this metric may occur at any time, and any blocking occurs at the
-	// expense of total performance of rendering all registered
-	// metrics. Ideally, Metric implementations should support concurrent
-	// readers.
-	//
-	// While populating dto.Metric, it is the responsibility of the
-	// implementation to ensure validity of the Metric protobuf (like valid
-	// UTF-8 strings or syntactically valid metric and label names). It is
-	// recommended to sort labels lexicographically. (Implementers may find
-	// LabelPairSorter useful for that.) Callers of Write should still make
-	// sure of sorting if they depend on it.
-	Write(*dto.Metric) error
-	// TODO(beorn7): The original rationale of passing in a pre-allocated
-	// dto.Metric protobuf to save allocations has disappeared. The
-	// signature of this method should be changed to "Write() (*dto.Metric,
-	// error)".
-}
-
-// Opts bundles the options for creating most Metric types. Each metric
-// implementation XXX has its own XXXOpts type, but in most cases, it is just be
-// an alias of this type (which might change when the requirement arises.)
-//
-// It is mandatory to set Name and Help to a non-empty string. All other fields
-// are optional and can safely be left at their zero value.
-type Opts struct {
-	// Namespace, Subsystem, and Name are components of the fully-qualified
-	// name of the Metric (created by joining these components with
-	// "_"). Only Name is mandatory, the others merely help structuring the
-	// name. Note that the fully-qualified name of the metric must be a
-	// valid Prometheus metric name.
-	Namespace string
-	Subsystem string
-	Name      string
-
-	// Help provides information about this metric. Mandatory!
-	//
-	// Metrics with the same fully-qualified name must have the same Help
-	// string.
-	Help string
-
-	// ConstLabels are used to attach fixed labels to this metric. Metrics
-	// with the same fully-qualified name must have the same label names in
-	// their ConstLabels.
-	//
-	// ConstLabels are only used rarely. In particular, do not use them to
-	// attach the same labels to all your metrics. Those use cases are
-	// better covered by target labels set by the scraping Prometheus
-	// server, or by one specific metric (e.g. a build_info or a
-	// machine_role metric). See also
-	// https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels
-	ConstLabels Labels
-}
-
-// BuildFQName joins the given three name components by "_". Empty name
-// components are ignored. If the name parameter itself is empty, an empty
-// string is returned, no matter what. Metric implementations included in this
-// library use this function internally to generate the fully-qualified metric
-// name from the name component in their Opts. Users of the library will only
-// need this function if they implement their own Metric or instantiate a Desc
-// (with NewDesc) directly.
-func BuildFQName(namespace, subsystem, name string) string {
-	if name == "" {
-		return ""
-	}
-	switch {
-	case namespace != "" && subsystem != "":
-		return strings.Join([]string{namespace, subsystem, name}, "_")
-	case namespace != "":
-		return strings.Join([]string{namespace, name}, "_")
-	case subsystem != "":
-		return strings.Join([]string{subsystem, name}, "_")
-	}
-	return name
-}
-
-// LabelPairSorter implements sort.Interface. It is used to sort a slice of
-// dto.LabelPair pointers. This is useful for implementing the Write method of
-// custom metrics.
-type LabelPairSorter []*dto.LabelPair
-
-func (s LabelPairSorter) Len() int {
-	return len(s)
-}
-
-func (s LabelPairSorter) Swap(i, j int) {
-	s[i], s[j] = s[j], s[i]
-}
-
-func (s LabelPairSorter) Less(i, j int) bool {
-	return s[i].GetName() < s[j].GetName()
-}
-
-type invalidMetric struct {
-	desc *Desc
-	err  error
-}
-
-// NewInvalidMetric returns a metric whose Write method always returns the
-// provided error. It is useful if a Collector finds itself unable to collect
-// a metric and wishes to report an error to the registry.
-func NewInvalidMetric(desc *Desc, err error) Metric {
-	return &invalidMetric{desc, err}
-}
-
-func (m *invalidMetric) Desc() *Desc { return m.desc }
-
-func (m *invalidMetric) Write(*dto.Metric) error { return m.err }
-
-type timestampedMetric struct {
-	Metric
-	t time.Time
-}
-
-func (m timestampedMetric) Write(pb *dto.Metric) error {
-	e := m.Metric.Write(pb)
-	pb.TimestampMs = proto.Int64(m.t.Unix()*1000 + int64(m.t.Nanosecond()/1000000))
-	return e
-}
-
-// NewMetricWithTimestamp returns a new Metric wrapping the provided Metric in a
-// way that it has an explicit timestamp set to the provided Time. This is only
-// useful in rare cases as the timestamp of a Prometheus metric should usually
-// be set by the Prometheus server during scraping. Exceptions include mirroring
-// metrics with given timestamps from other metric
-// sources.
-//
-// NewMetricWithTimestamp works best with MustNewConstMetric,
-// MustNewConstHistogram, and MustNewConstSummary, see example.
-//
-// Currently, the exposition formats used by Prometheus are limited to
-// millisecond resolution. Thus, the provided time will be rounded down to the
-// next full millisecond value.
-func NewMetricWithTimestamp(t time.Time, m Metric) Metric {
-	return timestampedMetric{Metric: m, t: t}
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/observer.go b/vendor/github.com/prometheus/client_golang/prometheus/observer.go
deleted file mode 100644
index 5806cd0..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/observer.go
+++ /dev/null
@@ -1,52 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-// Observer is the interface that wraps the Observe method, which is used by
-// Histogram and Summary to add observations.
-type Observer interface {
-	Observe(float64)
-}
-
-// The ObserverFunc type is an adapter to allow the use of ordinary
-// functions as Observers. If f is a function with the appropriate
-// signature, ObserverFunc(f) is an Observer that calls f.
-//
-// This adapter is usually used in connection with the Timer type, and there are
-// two general use cases:
-//
-// The most common one is to use a Gauge as the Observer for a Timer.
-// See the "Gauge" Timer example.
-//
-// The more advanced use case is to create a function that dynamically decides
-// which Observer to use for observing the duration. See the "Complex" Timer
-// example.
-type ObserverFunc func(float64)
-
-// Observe calls f(value). It implements Observer.
-func (f ObserverFunc) Observe(value float64) {
-	f(value)
-}
-
-// ObserverVec is an interface implemented by `HistogramVec` and `SummaryVec`.
-type ObserverVec interface {
-	GetMetricWith(Labels) (Observer, error)
-	GetMetricWithLabelValues(lvs ...string) (Observer, error)
-	With(Labels) Observer
-	WithLabelValues(...string) Observer
-	CurryWith(Labels) (ObserverVec, error)
-	MustCurryWith(Labels) ObserverVec
-
-	Collector
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go b/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go
deleted file mode 100644
index 5ab2b1c..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/process_collector.go
+++ /dev/null
@@ -1,147 +0,0 @@
-// Copyright 2015 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import "github.com/prometheus/procfs"
-
-type processCollector struct {
-	collectFn       func(chan<- Metric)
-	pidFn           func() (int, error)
-	cpuTotal        *Desc
-	openFDs, maxFDs *Desc
-	vsize, maxVsize *Desc
-	rss             *Desc
-	startTime       *Desc
-}
-
-// NewProcessCollector returns a collector which exports the current state of
-// process metrics including CPU, memory and file descriptor usage as well as
-// the process start time for the given process ID under the given namespace.
-//
-// Currently, the collector depends on a Linux-style proc filesystem and
-// therefore only exports metrics for Linux.
-func NewProcessCollector(pid int, namespace string) Collector {
-	return NewProcessCollectorPIDFn(
-		func() (int, error) { return pid, nil },
-		namespace,
-	)
-}
-
-// NewProcessCollectorPIDFn works like NewProcessCollector but the process ID is
-// determined on each collect anew by calling the given pidFn function.
-func NewProcessCollectorPIDFn(
-	pidFn func() (int, error),
-	namespace string,
-) Collector {
-	ns := ""
-	if len(namespace) > 0 {
-		ns = namespace + "_"
-	}
-
-	c := processCollector{
-		pidFn:     pidFn,
-		collectFn: func(chan<- Metric) {},
-
-		cpuTotal: NewDesc(
-			ns+"process_cpu_seconds_total",
-			"Total user and system CPU time spent in seconds.",
-			nil, nil,
-		),
-		openFDs: NewDesc(
-			ns+"process_open_fds",
-			"Number of open file descriptors.",
-			nil, nil,
-		),
-		maxFDs: NewDesc(
-			ns+"process_max_fds",
-			"Maximum number of open file descriptors.",
-			nil, nil,
-		),
-		vsize: NewDesc(
-			ns+"process_virtual_memory_bytes",
-			"Virtual memory size in bytes.",
-			nil, nil,
-		),
-		maxVsize: NewDesc(
-			ns+"process_virtual_memory_max_bytes",
-			"Maximum amount of virtual memory available in bytes.",
-			nil, nil,
-		),
-		rss: NewDesc(
-			ns+"process_resident_memory_bytes",
-			"Resident memory size in bytes.",
-			nil, nil,
-		),
-		startTime: NewDesc(
-			ns+"process_start_time_seconds",
-			"Start time of the process since unix epoch in seconds.",
-			nil, nil,
-		),
-	}
-
-	// Set up process metric collection if supported by the runtime.
-	if _, err := procfs.NewStat(); err == nil {
-		c.collectFn = c.processCollect
-	}
-
-	return &c
-}
-
-// Describe returns all descriptions of the collector.
-func (c *processCollector) Describe(ch chan<- *Desc) {
-	ch <- c.cpuTotal
-	ch <- c.openFDs
-	ch <- c.maxFDs
-	ch <- c.vsize
-	ch <- c.maxVsize
-	ch <- c.rss
-	ch <- c.startTime
-}
-
-// Collect returns the current state of all metrics of the collector.
-func (c *processCollector) Collect(ch chan<- Metric) {
-	c.collectFn(ch)
-}
-
-// TODO(ts): Bring back error reporting by reverting 7faf9e7 as soon as the
-// client allows users to configure the error behavior.
-func (c *processCollector) processCollect(ch chan<- Metric) {
-	pid, err := c.pidFn()
-	if err != nil {
-		return
-	}
-
-	p, err := procfs.NewProc(pid)
-	if err != nil {
-		return
-	}
-
-	if stat, err := p.NewStat(); err == nil {
-		ch <- MustNewConstMetric(c.cpuTotal, CounterValue, stat.CPUTime())
-		ch <- MustNewConstMetric(c.vsize, GaugeValue, float64(stat.VirtualMemory()))
-		ch <- MustNewConstMetric(c.rss, GaugeValue, float64(stat.ResidentMemory()))
-		if startTime, err := stat.StartTime(); err == nil {
-			ch <- MustNewConstMetric(c.startTime, GaugeValue, startTime)
-		}
-	}
-
-	if fds, err := p.FileDescriptorsLen(); err == nil {
-		ch <- MustNewConstMetric(c.openFDs, GaugeValue, float64(fds))
-	}
-
-	if limits, err := p.NewLimits(); err == nil {
-		ch <- MustNewConstMetric(c.maxFDs, GaugeValue, float64(limits.OpenFiles))
-		ch <- MustNewConstMetric(c.maxVsize, GaugeValue, float64(limits.AddressSpace))
-	}
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go
deleted file mode 100644
index 67b56d3..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator.go
+++ /dev/null
@@ -1,199 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package promhttp
-
-import (
-	"bufio"
-	"io"
-	"net"
-	"net/http"
-)
-
-const (
-	closeNotifier = 1 << iota
-	flusher
-	hijacker
-	readerFrom
-	pusher
-)
-
-type delegator interface {
-	http.ResponseWriter
-
-	Status() int
-	Written() int64
-}
-
-type responseWriterDelegator struct {
-	http.ResponseWriter
-
-	handler, method    string
-	status             int
-	written            int64
-	wroteHeader        bool
-	observeWriteHeader func(int)
-}
-
-func (r *responseWriterDelegator) Status() int {
-	return r.status
-}
-
-func (r *responseWriterDelegator) Written() int64 {
-	return r.written
-}
-
-func (r *responseWriterDelegator) WriteHeader(code int) {
-	r.status = code
-	r.wroteHeader = true
-	r.ResponseWriter.WriteHeader(code)
-	if r.observeWriteHeader != nil {
-		r.observeWriteHeader(code)
-	}
-}
-
-func (r *responseWriterDelegator) Write(b []byte) (int, error) {
-	if !r.wroteHeader {
-		r.WriteHeader(http.StatusOK)
-	}
-	n, err := r.ResponseWriter.Write(b)
-	r.written += int64(n)
-	return n, err
-}
-
-type closeNotifierDelegator struct{ *responseWriterDelegator }
-type flusherDelegator struct{ *responseWriterDelegator }
-type hijackerDelegator struct{ *responseWriterDelegator }
-type readerFromDelegator struct{ *responseWriterDelegator }
-
-func (d closeNotifierDelegator) CloseNotify() <-chan bool {
-	return d.ResponseWriter.(http.CloseNotifier).CloseNotify()
-}
-func (d flusherDelegator) Flush() {
-	d.ResponseWriter.(http.Flusher).Flush()
-}
-func (d hijackerDelegator) Hijack() (net.Conn, *bufio.ReadWriter, error) {
-	return d.ResponseWriter.(http.Hijacker).Hijack()
-}
-func (d readerFromDelegator) ReadFrom(re io.Reader) (int64, error) {
-	if !d.wroteHeader {
-		d.WriteHeader(http.StatusOK)
-	}
-	n, err := d.ResponseWriter.(io.ReaderFrom).ReadFrom(re)
-	d.written += n
-	return n, err
-}
-
-var pickDelegator = make([]func(*responseWriterDelegator) delegator, 32)
-
-func init() {
-	// TODO(beorn7): Code generation would help here.
-	pickDelegator[0] = func(d *responseWriterDelegator) delegator { // 0
-		return d
-	}
-	pickDelegator[closeNotifier] = func(d *responseWriterDelegator) delegator { // 1
-		return closeNotifierDelegator{d}
-	}
-	pickDelegator[flusher] = func(d *responseWriterDelegator) delegator { // 2
-		return flusherDelegator{d}
-	}
-	pickDelegator[flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 3
-		return struct {
-			*responseWriterDelegator
-			http.Flusher
-			http.CloseNotifier
-		}{d, flusherDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[hijacker] = func(d *responseWriterDelegator) delegator { // 4
-		return hijackerDelegator{d}
-	}
-	pickDelegator[hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 5
-		return struct {
-			*responseWriterDelegator
-			http.Hijacker
-			http.CloseNotifier
-		}{d, hijackerDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 6
-		return struct {
-			*responseWriterDelegator
-			http.Hijacker
-			http.Flusher
-		}{d, hijackerDelegator{d}, flusherDelegator{d}}
-	}
-	pickDelegator[hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 7
-		return struct {
-			*responseWriterDelegator
-			http.Hijacker
-			http.Flusher
-			http.CloseNotifier
-		}{d, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[readerFrom] = func(d *responseWriterDelegator) delegator { // 8
-		return readerFromDelegator{d}
-	}
-	pickDelegator[readerFrom+closeNotifier] = func(d *responseWriterDelegator) delegator { // 9
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.CloseNotifier
-		}{d, readerFromDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[readerFrom+flusher] = func(d *responseWriterDelegator) delegator { // 10
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.Flusher
-		}{d, readerFromDelegator{d}, flusherDelegator{d}}
-	}
-	pickDelegator[readerFrom+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 11
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.Flusher
-			http.CloseNotifier
-		}{d, readerFromDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[readerFrom+hijacker] = func(d *responseWriterDelegator) delegator { // 12
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.Hijacker
-		}{d, readerFromDelegator{d}, hijackerDelegator{d}}
-	}
-	pickDelegator[readerFrom+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 13
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.Hijacker
-			http.CloseNotifier
-		}{d, readerFromDelegator{d}, hijackerDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[readerFrom+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 14
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.Hijacker
-			http.Flusher
-		}{d, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}}
-	}
-	pickDelegator[readerFrom+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 15
-		return struct {
-			*responseWriterDelegator
-			io.ReaderFrom
-			http.Hijacker
-			http.Flusher
-			http.CloseNotifier
-		}{d, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
-	}
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_1_8.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_1_8.go
deleted file mode 100644
index 31a7069..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_1_8.go
+++ /dev/null
@@ -1,181 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build go1.8
-
-package promhttp
-
-import (
-	"io"
-	"net/http"
-)
-
-type pusherDelegator struct{ *responseWriterDelegator }
-
-func (d pusherDelegator) Push(target string, opts *http.PushOptions) error {
-	return d.ResponseWriter.(http.Pusher).Push(target, opts)
-}
-
-func init() {
-	pickDelegator[pusher] = func(d *responseWriterDelegator) delegator { // 16
-		return pusherDelegator{d}
-	}
-	pickDelegator[pusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 17
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.CloseNotifier
-		}{d, pusherDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+flusher] = func(d *responseWriterDelegator) delegator { // 18
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.Flusher
-		}{d, pusherDelegator{d}, flusherDelegator{d}}
-	}
-	pickDelegator[pusher+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 19
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.Flusher
-			http.CloseNotifier
-		}{d, pusherDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+hijacker] = func(d *responseWriterDelegator) delegator { // 20
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.Hijacker
-		}{d, pusherDelegator{d}, hijackerDelegator{d}}
-	}
-	pickDelegator[pusher+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 21
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.Hijacker
-			http.CloseNotifier
-		}{d, pusherDelegator{d}, hijackerDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 22
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.Hijacker
-			http.Flusher
-		}{d, pusherDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}}
-	}
-	pickDelegator[pusher+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { //23
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			http.Hijacker
-			http.Flusher
-			http.CloseNotifier
-		}{d, pusherDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom] = func(d *responseWriterDelegator) delegator { // 24
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-		}{d, pusherDelegator{d}, readerFromDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+closeNotifier] = func(d *responseWriterDelegator) delegator { // 25
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.CloseNotifier
-		}{d, pusherDelegator{d}, readerFromDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+flusher] = func(d *responseWriterDelegator) delegator { // 26
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.Flusher
-		}{d, pusherDelegator{d}, readerFromDelegator{d}, flusherDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 27
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.Flusher
-			http.CloseNotifier
-		}{d, pusherDelegator{d}, readerFromDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+hijacker] = func(d *responseWriterDelegator) delegator { // 28
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.Hijacker
-		}{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+hijacker+closeNotifier] = func(d *responseWriterDelegator) delegator { // 29
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.Hijacker
-			http.CloseNotifier
-		}{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}, closeNotifierDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+hijacker+flusher] = func(d *responseWriterDelegator) delegator { // 30
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.Hijacker
-			http.Flusher
-		}{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}}
-	}
-	pickDelegator[pusher+readerFrom+hijacker+flusher+closeNotifier] = func(d *responseWriterDelegator) delegator { // 31
-		return struct {
-			*responseWriterDelegator
-			http.Pusher
-			io.ReaderFrom
-			http.Hijacker
-			http.Flusher
-			http.CloseNotifier
-		}{d, pusherDelegator{d}, readerFromDelegator{d}, hijackerDelegator{d}, flusherDelegator{d}, closeNotifierDelegator{d}}
-	}
-}
-
-func newDelegator(w http.ResponseWriter, observeWriteHeaderFunc func(int)) delegator {
-	d := &responseWriterDelegator{
-		ResponseWriter:     w,
-		observeWriteHeader: observeWriteHeaderFunc,
-	}
-
-	id := 0
-	if _, ok := w.(http.CloseNotifier); ok {
-		id += closeNotifier
-	}
-	if _, ok := w.(http.Flusher); ok {
-		id += flusher
-	}
-	if _, ok := w.(http.Hijacker); ok {
-		id += hijacker
-	}
-	if _, ok := w.(io.ReaderFrom); ok {
-		id += readerFrom
-	}
-	if _, ok := w.(http.Pusher); ok {
-		id += pusher
-	}
-
-	return pickDelegator[id](d)
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_pre_1_8.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_pre_1_8.go
deleted file mode 100644
index 8bb9b8b..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/delegator_pre_1_8.go
+++ /dev/null
@@ -1,44 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build !go1.8
-
-package promhttp
-
-import (
-	"io"
-	"net/http"
-)
-
-func newDelegator(w http.ResponseWriter, observeWriteHeaderFunc func(int)) delegator {
-	d := &responseWriterDelegator{
-		ResponseWriter:     w,
-		observeWriteHeader: observeWriteHeaderFunc,
-	}
-
-	id := 0
-	if _, ok := w.(http.CloseNotifier); ok {
-		id += closeNotifier
-	}
-	if _, ok := w.(http.Flusher); ok {
-		id += flusher
-	}
-	if _, ok := w.(http.Hijacker); ok {
-		id += hijacker
-	}
-	if _, ok := w.(io.ReaderFrom); ok {
-		id += readerFrom
-	}
-
-	return pickDelegator[id](d)
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go
deleted file mode 100644
index 0135737..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/http.go
+++ /dev/null
@@ -1,311 +0,0 @@
-// Copyright 2016 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// Package promhttp provides tooling around HTTP servers and clients.
-//
-// First, the package allows the creation of http.Handler instances to expose
-// Prometheus metrics via HTTP. promhttp.Handler acts on the
-// prometheus.DefaultGatherer. With HandlerFor, you can create a handler for a
-// custom registry or anything that implements the Gatherer interface. It also
-// allows the creation of handlers that act differently on errors or allow to
-// log errors.
-//
-// Second, the package provides tooling to instrument instances of http.Handler
-// via middleware. Middleware wrappers follow the naming scheme
-// InstrumentHandlerX, where X describes the intended use of the middleware.
-// See each function's doc comment for specific details.
-//
-// Finally, the package allows for an http.RoundTripper to be instrumented via
-// middleware. Middleware wrappers follow the naming scheme
-// InstrumentRoundTripperX, where X describes the intended use of the
-// middleware. See each function's doc comment for specific details.
-package promhttp
-
-import (
-	"bytes"
-	"compress/gzip"
-	"fmt"
-	"io"
-	"net/http"
-	"strings"
-	"sync"
-	"time"
-
-	"github.com/prometheus/common/expfmt"
-
-	"github.com/prometheus/client_golang/prometheus"
-)
-
-const (
-	contentTypeHeader     = "Content-Type"
-	contentLengthHeader   = "Content-Length"
-	contentEncodingHeader = "Content-Encoding"
-	acceptEncodingHeader  = "Accept-Encoding"
-)
-
-var bufPool sync.Pool
-
-func getBuf() *bytes.Buffer {
-	buf := bufPool.Get()
-	if buf == nil {
-		return &bytes.Buffer{}
-	}
-	return buf.(*bytes.Buffer)
-}
-
-func giveBuf(buf *bytes.Buffer) {
-	buf.Reset()
-	bufPool.Put(buf)
-}
-
-// Handler returns an http.Handler for the prometheus.DefaultGatherer, using
-// default HandlerOpts, i.e. it reports the first error as an HTTP error, it has
-// no error logging, and it applies compression if requested by the client.
-//
-// The returned http.Handler is already instrumented using the
-// InstrumentMetricHandler function and the prometheus.DefaultRegisterer. If you
-// create multiple http.Handlers by separate calls of the Handler function, the
-// metrics used for instrumentation will be shared between them, providing
-// global scrape counts.
-//
-// This function is meant to cover the bulk of basic use cases. If you are doing
-// anything that requires more customization (including using a non-default
-// Gatherer, different instrumentation, and non-default HandlerOpts), use the
-// HandlerFor function. See there for details.
-func Handler() http.Handler {
-	return InstrumentMetricHandler(
-		prometheus.DefaultRegisterer, HandlerFor(prometheus.DefaultGatherer, HandlerOpts{}),
-	)
-}
-
-// HandlerFor returns an uninstrumented http.Handler for the provided
-// Gatherer. The behavior of the Handler is defined by the provided
-// HandlerOpts. Thus, HandlerFor is useful to create http.Handlers for custom
-// Gatherers, with non-default HandlerOpts, and/or with custom (or no)
-// instrumentation. Use the InstrumentMetricHandler function to apply the same
-// kind of instrumentation as it is used by the Handler function.
-func HandlerFor(reg prometheus.Gatherer, opts HandlerOpts) http.Handler {
-	var inFlightSem chan struct{}
-	if opts.MaxRequestsInFlight > 0 {
-		inFlightSem = make(chan struct{}, opts.MaxRequestsInFlight)
-	}
-
-	h := http.HandlerFunc(func(w http.ResponseWriter, req *http.Request) {
-		if inFlightSem != nil {
-			select {
-			case inFlightSem <- struct{}{}: // All good, carry on.
-				defer func() { <-inFlightSem }()
-			default:
-				http.Error(w, fmt.Sprintf(
-					"Limit of concurrent requests reached (%d), try again later.", opts.MaxRequestsInFlight,
-				), http.StatusServiceUnavailable)
-				return
-			}
-		}
-
-		mfs, err := reg.Gather()
-		if err != nil {
-			if opts.ErrorLog != nil {
-				opts.ErrorLog.Println("error gathering metrics:", err)
-			}
-			switch opts.ErrorHandling {
-			case PanicOnError:
-				panic(err)
-			case ContinueOnError:
-				if len(mfs) == 0 {
-					http.Error(w, "No metrics gathered, last error:\n\n"+err.Error(), http.StatusInternalServerError)
-					return
-				}
-			case HTTPErrorOnError:
-				http.Error(w, "An error has occurred during metrics gathering:\n\n"+err.Error(), http.StatusInternalServerError)
-				return
-			}
-		}
-
-		contentType := expfmt.Negotiate(req.Header)
-		buf := getBuf()
-		defer giveBuf(buf)
-		writer, encoding := decorateWriter(req, buf, opts.DisableCompression)
-		enc := expfmt.NewEncoder(writer, contentType)
-		var lastErr error
-		for _, mf := range mfs {
-			if err := enc.Encode(mf); err != nil {
-				lastErr = err
-				if opts.ErrorLog != nil {
-					opts.ErrorLog.Println("error encoding metric family:", err)
-				}
-				switch opts.ErrorHandling {
-				case PanicOnError:
-					panic(err)
-				case ContinueOnError:
-					// Handled later.
-				case HTTPErrorOnError:
-					http.Error(w, "An error has occurred during metrics encoding:\n\n"+err.Error(), http.StatusInternalServerError)
-					return
-				}
-			}
-		}
-		if closer, ok := writer.(io.Closer); ok {
-			closer.Close()
-		}
-		if lastErr != nil && buf.Len() == 0 {
-			http.Error(w, "No metrics encoded, last error:\n\n"+lastErr.Error(), http.StatusInternalServerError)
-			return
-		}
-		header := w.Header()
-		header.Set(contentTypeHeader, string(contentType))
-		header.Set(contentLengthHeader, fmt.Sprint(buf.Len()))
-		if encoding != "" {
-			header.Set(contentEncodingHeader, encoding)
-		}
-		if _, err := w.Write(buf.Bytes()); err != nil && opts.ErrorLog != nil {
-			opts.ErrorLog.Println("error while sending encoded metrics:", err)
-		}
-		// TODO(beorn7): Consider streaming serving of metrics.
-	})
-
-	if opts.Timeout <= 0 {
-		return h
-	}
-	return http.TimeoutHandler(h, opts.Timeout, fmt.Sprintf(
-		"Exceeded configured timeout of %v.\n",
-		opts.Timeout,
-	))
-}
-
-// InstrumentMetricHandler is usually used with an http.Handler returned by the
-// HandlerFor function. It instruments the provided http.Handler with two
-// metrics: A counter vector "promhttp_metric_handler_requests_total" to count
-// scrapes partitioned by HTTP status code, and a gauge
-// "promhttp_metric_handler_requests_in_flight" to track the number of
-// simultaneous scrapes. This function idempotently registers collectors for
-// both metrics with the provided Registerer. It panics if the registration
-// fails. The provided metrics are useful to see how many scrapes hit the
-// monitored target (which could be from different Prometheus servers or other
-// scrapers), and how often they overlap (which would result in more than one
-// scrape in flight at the same time). Note that the scrapes-in-flight gauge
-// will contain the scrape by which it is exposed, while the scrape counter will
-// only get incremented after the scrape is complete (as only then the status
-// code is known). For tracking scrape durations, use the
-// "scrape_duration_seconds" gauge created by the Prometheus server upon each
-// scrape.
-func InstrumentMetricHandler(reg prometheus.Registerer, handler http.Handler) http.Handler {
-	cnt := prometheus.NewCounterVec(
-		prometheus.CounterOpts{
-			Name: "promhttp_metric_handler_requests_total",
-			Help: "Total number of scrapes by HTTP status code.",
-		},
-		[]string{"code"},
-	)
-	// Initialize the most likely HTTP status codes.
-	cnt.WithLabelValues("200")
-	cnt.WithLabelValues("500")
-	cnt.WithLabelValues("503")
-	if err := reg.Register(cnt); err != nil {
-		if are, ok := err.(prometheus.AlreadyRegisteredError); ok {
-			cnt = are.ExistingCollector.(*prometheus.CounterVec)
-		} else {
-			panic(err)
-		}
-	}
-
-	gge := prometheus.NewGauge(prometheus.GaugeOpts{
-		Name: "promhttp_metric_handler_requests_in_flight",
-		Help: "Current number of scrapes being served.",
-	})
-	if err := reg.Register(gge); err != nil {
-		if are, ok := err.(prometheus.AlreadyRegisteredError); ok {
-			gge = are.ExistingCollector.(prometheus.Gauge)
-		} else {
-			panic(err)
-		}
-	}
-
-	return InstrumentHandlerCounter(cnt, InstrumentHandlerInFlight(gge, handler))
-}
-
-// HandlerErrorHandling defines how a Handler serving metrics will handle
-// errors.
-type HandlerErrorHandling int
-
-// These constants cause handlers serving metrics to behave as described if
-// errors are encountered.
-const (
-	// Serve an HTTP status code 500 upon the first error
-	// encountered. Report the error message in the body.
-	HTTPErrorOnError HandlerErrorHandling = iota
-	// Ignore errors and try to serve as many metrics as possible.  However,
-	// if no metrics can be served, serve an HTTP status code 500 and the
-	// last error message in the body. Only use this in deliberate "best
-	// effort" metrics collection scenarios. It is recommended to at least
-	// log errors (by providing an ErrorLog in HandlerOpts) to not mask
-	// errors completely.
-	ContinueOnError
-	// Panic upon the first error encountered (useful for "crash only" apps).
-	PanicOnError
-)
-
-// Logger is the minimal interface HandlerOpts needs for logging. Note that
-// log.Logger from the standard library implements this interface, and it is
-// easy to implement by custom loggers, if they don't do so already anyway.
-type Logger interface {
-	Println(v ...interface{})
-}
-
-// HandlerOpts specifies options how to serve metrics via an http.Handler. The
-// zero value of HandlerOpts is a reasonable default.
-type HandlerOpts struct {
-	// ErrorLog specifies an optional logger for errors collecting and
-	// serving metrics. If nil, errors are not logged at all.
-	ErrorLog Logger
-	// ErrorHandling defines how errors are handled. Note that errors are
-	// logged regardless of the configured ErrorHandling provided ErrorLog
-	// is not nil.
-	ErrorHandling HandlerErrorHandling
-	// If DisableCompression is true, the handler will never compress the
-	// response, even if requested by the client.
-	DisableCompression bool
-	// The number of concurrent HTTP requests is limited to
-	// MaxRequestsInFlight. Additional requests are responded to with 503
-	// Service Unavailable and a suitable message in the body. If
-	// MaxRequestsInFlight is 0 or negative, no limit is applied.
-	MaxRequestsInFlight int
-	// If handling a request takes longer than Timeout, it is responded to
-	// with 503 ServiceUnavailable and a suitable Message. No timeout is
-	// applied if Timeout is 0 or negative. Note that with the current
-	// implementation, reaching the timeout simply ends the HTTP requests as
-	// described above (and even that only if sending of the body hasn't
-	// started yet), while the bulk work of gathering all the metrics keeps
-	// running in the background (with the eventual result to be thrown
-	// away). Until the implementation is improved, it is recommended to
-	// implement a separate timeout in potentially slow Collectors.
-	Timeout time.Duration
-}
-
-// decorateWriter wraps a writer to handle gzip compression if requested.  It
-// returns the decorated writer and the appropriate "Content-Encoding" header
-// (which is empty if no compression is enabled).
-func decorateWriter(request *http.Request, writer io.Writer, compressionDisabled bool) (io.Writer, string) {
-	if compressionDisabled {
-		return writer, ""
-	}
-	header := request.Header.Get(acceptEncodingHeader)
-	parts := strings.Split(header, ",")
-	for _, part := range parts {
-		part = strings.TrimSpace(part)
-		if part == "gzip" || strings.HasPrefix(part, "gzip;") {
-			return gzip.NewWriter(writer), "gzip"
-		}
-	}
-	return writer, ""
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go
deleted file mode 100644
index 86fd564..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client.go
+++ /dev/null
@@ -1,97 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package promhttp
-
-import (
-	"net/http"
-	"time"
-
-	"github.com/prometheus/client_golang/prometheus"
-)
-
-// The RoundTripperFunc type is an adapter to allow the use of ordinary
-// functions as RoundTrippers. If f is a function with the appropriate
-// signature, RountTripperFunc(f) is a RoundTripper that calls f.
-type RoundTripperFunc func(req *http.Request) (*http.Response, error)
-
-// RoundTrip implements the RoundTripper interface.
-func (rt RoundTripperFunc) RoundTrip(r *http.Request) (*http.Response, error) {
-	return rt(r)
-}
-
-// InstrumentRoundTripperInFlight is a middleware that wraps the provided
-// http.RoundTripper. It sets the provided prometheus.Gauge to the number of
-// requests currently handled by the wrapped http.RoundTripper.
-//
-// See the example for ExampleInstrumentRoundTripperDuration for example usage.
-func InstrumentRoundTripperInFlight(gauge prometheus.Gauge, next http.RoundTripper) RoundTripperFunc {
-	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
-		gauge.Inc()
-		defer gauge.Dec()
-		return next.RoundTrip(r)
-	})
-}
-
-// InstrumentRoundTripperCounter is a middleware that wraps the provided
-// http.RoundTripper to observe the request result with the provided CounterVec.
-// The CounterVec must have zero, one, or two non-const non-curried labels. For
-// those, the only allowed label names are "code" and "method". The function
-// panics otherwise. Partitioning of the CounterVec happens by HTTP status code
-// and/or HTTP method if the respective instance label names are present in the
-// CounterVec. For unpartitioned counting, use a CounterVec with zero labels.
-//
-// If the wrapped RoundTripper panics or returns a non-nil error, the Counter
-// is not incremented.
-//
-// See the example for ExampleInstrumentRoundTripperDuration for example usage.
-func InstrumentRoundTripperCounter(counter *prometheus.CounterVec, next http.RoundTripper) RoundTripperFunc {
-	code, method := checkLabels(counter)
-
-	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
-		resp, err := next.RoundTrip(r)
-		if err == nil {
-			counter.With(labels(code, method, r.Method, resp.StatusCode)).Inc()
-		}
-		return resp, err
-	})
-}
-
-// InstrumentRoundTripperDuration is a middleware that wraps the provided
-// http.RoundTripper to observe the request duration with the provided
-// ObserverVec.  The ObserverVec must have zero, one, or two non-const
-// non-curried labels. For those, the only allowed label names are "code" and
-// "method". The function panics otherwise. The Observe method of the Observer
-// in the ObserverVec is called with the request duration in
-// seconds. Partitioning happens by HTTP status code and/or HTTP method if the
-// respective instance label names are present in the ObserverVec. For
-// unpartitioned observations, use an ObserverVec with zero labels. Note that
-// partitioning of Histograms is expensive and should be used judiciously.
-//
-// If the wrapped RoundTripper panics or returns a non-nil error, no values are
-// reported.
-//
-// Note that this method is only guaranteed to never observe negative durations
-// if used with Go1.9+.
-func InstrumentRoundTripperDuration(obs prometheus.ObserverVec, next http.RoundTripper) RoundTripperFunc {
-	code, method := checkLabels(obs)
-
-	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
-		start := time.Now()
-		resp, err := next.RoundTrip(r)
-		if err == nil {
-			obs.With(labels(code, method, r.Method, resp.StatusCode)).Observe(time.Since(start).Seconds())
-		}
-		return resp, err
-	})
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client_1_8.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client_1_8.go
deleted file mode 100644
index a034d1e..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_client_1_8.go
+++ /dev/null
@@ -1,144 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-// +build go1.8
-
-package promhttp
-
-import (
-	"context"
-	"crypto/tls"
-	"net/http"
-	"net/http/httptrace"
-	"time"
-)
-
-// InstrumentTrace is used to offer flexibility in instrumenting the available
-// httptrace.ClientTrace hook functions. Each function is passed a float64
-// representing the time in seconds since the start of the http request. A user
-// may choose to use separately buckets Histograms, or implement custom
-// instance labels on a per function basis.
-type InstrumentTrace struct {
-	GotConn              func(float64)
-	PutIdleConn          func(float64)
-	GotFirstResponseByte func(float64)
-	Got100Continue       func(float64)
-	DNSStart             func(float64)
-	DNSDone              func(float64)
-	ConnectStart         func(float64)
-	ConnectDone          func(float64)
-	TLSHandshakeStart    func(float64)
-	TLSHandshakeDone     func(float64)
-	WroteHeaders         func(float64)
-	Wait100Continue      func(float64)
-	WroteRequest         func(float64)
-}
-
-// InstrumentRoundTripperTrace is a middleware that wraps the provided
-// RoundTripper and reports times to hook functions provided in the
-// InstrumentTrace struct. Hook functions that are not present in the provided
-// InstrumentTrace struct are ignored. Times reported to the hook functions are
-// time since the start of the request. Only with Go1.9+, those times are
-// guaranteed to never be negative. (Earlier Go versions are not using a
-// monotonic clock.) Note that partitioning of Histograms is expensive and
-// should be used judiciously.
-//
-// For hook functions that receive an error as an argument, no observations are
-// made in the event of a non-nil error value.
-//
-// See the example for ExampleInstrumentRoundTripperDuration for example usage.
-func InstrumentRoundTripperTrace(it *InstrumentTrace, next http.RoundTripper) RoundTripperFunc {
-	return RoundTripperFunc(func(r *http.Request) (*http.Response, error) {
-		start := time.Now()
-
-		trace := &httptrace.ClientTrace{
-			GotConn: func(_ httptrace.GotConnInfo) {
-				if it.GotConn != nil {
-					it.GotConn(time.Since(start).Seconds())
-				}
-			},
-			PutIdleConn: func(err error) {
-				if err != nil {
-					return
-				}
-				if it.PutIdleConn != nil {
-					it.PutIdleConn(time.Since(start).Seconds())
-				}
-			},
-			DNSStart: func(_ httptrace.DNSStartInfo) {
-				if it.DNSStart != nil {
-					it.DNSStart(time.Since(start).Seconds())
-				}
-			},
-			DNSDone: func(_ httptrace.DNSDoneInfo) {
-				if it.DNSDone != nil {
-					it.DNSDone(time.Since(start).Seconds())
-				}
-			},
-			ConnectStart: func(_, _ string) {
-				if it.ConnectStart != nil {
-					it.ConnectStart(time.Since(start).Seconds())
-				}
-			},
-			ConnectDone: func(_, _ string, err error) {
-				if err != nil {
-					return
-				}
-				if it.ConnectDone != nil {
-					it.ConnectDone(time.Since(start).Seconds())
-				}
-			},
-			GotFirstResponseByte: func() {
-				if it.GotFirstResponseByte != nil {
-					it.GotFirstResponseByte(time.Since(start).Seconds())
-				}
-			},
-			Got100Continue: func() {
-				if it.Got100Continue != nil {
-					it.Got100Continue(time.Since(start).Seconds())
-				}
-			},
-			TLSHandshakeStart: func() {
-				if it.TLSHandshakeStart != nil {
-					it.TLSHandshakeStart(time.Since(start).Seconds())
-				}
-			},
-			TLSHandshakeDone: func(_ tls.ConnectionState, err error) {
-				if err != nil {
-					return
-				}
-				if it.TLSHandshakeDone != nil {
-					it.TLSHandshakeDone(time.Since(start).Seconds())
-				}
-			},
-			WroteHeaders: func() {
-				if it.WroteHeaders != nil {
-					it.WroteHeaders(time.Since(start).Seconds())
-				}
-			},
-			Wait100Continue: func() {
-				if it.Wait100Continue != nil {
-					it.Wait100Continue(time.Since(start).Seconds())
-				}
-			},
-			WroteRequest: func(_ httptrace.WroteRequestInfo) {
-				if it.WroteRequest != nil {
-					it.WroteRequest(time.Since(start).Seconds())
-				}
-			},
-		}
-		r = r.WithContext(httptrace.WithClientTrace(context.Background(), trace))
-
-		return next.RoundTrip(r)
-	})
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go b/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go
deleted file mode 100644
index 9db2438..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/promhttp/instrument_server.go
+++ /dev/null
@@ -1,447 +0,0 @@
-// Copyright 2017 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package promhttp
-
-import (
-	"errors"
-	"net/http"
-	"strconv"
-	"strings"
-	"time"
-
-	dto "github.com/prometheus/client_model/go"
-
-	"github.com/prometheus/client_golang/prometheus"
-)
-
-// magicString is used for the hacky label test in checkLabels. Remove once fixed.
-const magicString = "zZgWfBxLqvG8kc8IMv3POi2Bb0tZI3vAnBx+gBaFi9FyPzB/CzKUer1yufDa"
-
-// InstrumentHandlerInFlight is a middleware that wraps the provided
-// http.Handler. It sets the provided prometheus.Gauge to the number of
-// requests currently handled by the wrapped http.Handler.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerInFlight(g prometheus.Gauge, next http.Handler) http.Handler {
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		g.Inc()
-		defer g.Dec()
-		next.ServeHTTP(w, r)
-	})
-}
-
-// InstrumentHandlerDuration is a middleware that wraps the provided
-// http.Handler to observe the request duration with the provided ObserverVec.
-// The ObserverVec must have zero, one, or two non-const non-curried labels. For
-// those, the only allowed label names are "code" and "method". The function
-// panics otherwise. The Observe method of the Observer in the ObserverVec is
-// called with the request duration in seconds. Partitioning happens by HTTP
-// status code and/or HTTP method if the respective instance label names are
-// present in the ObserverVec. For unpartitioned observations, use an
-// ObserverVec with zero labels. Note that partitioning of Histograms is
-// expensive and should be used judiciously.
-//
-// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
-//
-// If the wrapped Handler panics, no values are reported.
-//
-// Note that this method is only guaranteed to never observe negative durations
-// if used with Go1.9+.
-func InstrumentHandlerDuration(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc {
-	code, method := checkLabels(obs)
-
-	if code {
-		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			now := time.Now()
-			d := newDelegator(w, nil)
-			next.ServeHTTP(d, r)
-
-			obs.With(labels(code, method, r.Method, d.Status())).Observe(time.Since(now).Seconds())
-		})
-	}
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		now := time.Now()
-		next.ServeHTTP(w, r)
-		obs.With(labels(code, method, r.Method, 0)).Observe(time.Since(now).Seconds())
-	})
-}
-
-// InstrumentHandlerCounter is a middleware that wraps the provided http.Handler
-// to observe the request result with the provided CounterVec.  The CounterVec
-// must have zero, one, or two non-const non-curried labels. For those, the only
-// allowed label names are "code" and "method". The function panics
-// otherwise. Partitioning of the CounterVec happens by HTTP status code and/or
-// HTTP method if the respective instance label names are present in the
-// CounterVec. For unpartitioned counting, use a CounterVec with zero labels.
-//
-// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
-//
-// If the wrapped Handler panics, the Counter is not incremented.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerCounter(counter *prometheus.CounterVec, next http.Handler) http.HandlerFunc {
-	code, method := checkLabels(counter)
-
-	if code {
-		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			d := newDelegator(w, nil)
-			next.ServeHTTP(d, r)
-			counter.With(labels(code, method, r.Method, d.Status())).Inc()
-		})
-	}
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		next.ServeHTTP(w, r)
-		counter.With(labels(code, method, r.Method, 0)).Inc()
-	})
-}
-
-// InstrumentHandlerTimeToWriteHeader is a middleware that wraps the provided
-// http.Handler to observe with the provided ObserverVec the request duration
-// until the response headers are written. The ObserverVec must have zero, one,
-// or two non-const non-curried labels. For those, the only allowed label names
-// are "code" and "method". The function panics otherwise. The Observe method of
-// the Observer in the ObserverVec is called with the request duration in
-// seconds. Partitioning happens by HTTP status code and/or HTTP method if the
-// respective instance label names are present in the ObserverVec. For
-// unpartitioned observations, use an ObserverVec with zero labels. Note that
-// partitioning of Histograms is expensive and should be used judiciously.
-//
-// If the wrapped Handler panics before calling WriteHeader, no value is
-// reported.
-//
-// Note that this method is only guaranteed to never observe negative durations
-// if used with Go1.9+.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerTimeToWriteHeader(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc {
-	code, method := checkLabels(obs)
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		now := time.Now()
-		d := newDelegator(w, func(status int) {
-			obs.With(labels(code, method, r.Method, status)).Observe(time.Since(now).Seconds())
-		})
-		next.ServeHTTP(d, r)
-	})
-}
-
-// InstrumentHandlerRequestSize is a middleware that wraps the provided
-// http.Handler to observe the request size with the provided ObserverVec.  The
-// ObserverVec must have zero, one, or two non-const non-curried labels. For
-// those, the only allowed label names are "code" and "method". The function
-// panics otherwise. The Observe method of the Observer in the ObserverVec is
-// called with the request size in bytes. Partitioning happens by HTTP status
-// code and/or HTTP method if the respective instance label names are present in
-// the ObserverVec. For unpartitioned observations, use an ObserverVec with zero
-// labels. Note that partitioning of Histograms is expensive and should be used
-// judiciously.
-//
-// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
-//
-// If the wrapped Handler panics, no values are reported.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerRequestSize(obs prometheus.ObserverVec, next http.Handler) http.HandlerFunc {
-	code, method := checkLabels(obs)
-
-	if code {
-		return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-			d := newDelegator(w, nil)
-			next.ServeHTTP(d, r)
-			size := computeApproximateRequestSize(r)
-			obs.With(labels(code, method, r.Method, d.Status())).Observe(float64(size))
-		})
-	}
-
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		next.ServeHTTP(w, r)
-		size := computeApproximateRequestSize(r)
-		obs.With(labels(code, method, r.Method, 0)).Observe(float64(size))
-	})
-}
-
-// InstrumentHandlerResponseSize is a middleware that wraps the provided
-// http.Handler to observe the response size with the provided ObserverVec.  The
-// ObserverVec must have zero, one, or two non-const non-curried labels. For
-// those, the only allowed label names are "code" and "method". The function
-// panics otherwise. The Observe method of the Observer in the ObserverVec is
-// called with the response size in bytes. Partitioning happens by HTTP status
-// code and/or HTTP method if the respective instance label names are present in
-// the ObserverVec. For unpartitioned observations, use an ObserverVec with zero
-// labels. Note that partitioning of Histograms is expensive and should be used
-// judiciously.
-//
-// If the wrapped Handler does not set a status code, a status code of 200 is assumed.
-//
-// If the wrapped Handler panics, no values are reported.
-//
-// See the example for InstrumentHandlerDuration for example usage.
-func InstrumentHandlerResponseSize(obs prometheus.ObserverVec, next http.Handler) http.Handler {
-	code, method := checkLabels(obs)
-	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
-		d := newDelegator(w, nil)
-		next.ServeHTTP(d, r)
-		obs.With(labels(code, method, r.Method, d.Status())).Observe(float64(d.Written()))
-	})
-}
-
-func checkLabels(c prometheus.Collector) (code bool, method bool) {
-	// TODO(beorn7): Remove this hacky way to check for instance labels
-	// once Descriptors can have their dimensionality queried.
-	var (
-		desc *prometheus.Desc
-		m    prometheus.Metric
-		pm   dto.Metric
-		lvs  []string
-	)
-
-	// Get the Desc from the Collector.
-	descc := make(chan *prometheus.Desc, 1)
-	c.Describe(descc)
-
-	select {
-	case desc = <-descc:
-	default:
-		panic("no description provided by collector")
-	}
-	select {
-	case <-descc:
-		panic("more than one description provided by collector")
-	default:
-	}
-
-	close(descc)
-
-	// Create a ConstMetric with the Desc. Since we don't know how many
-	// variable labels there are, try for as long as it needs.
-	for err := errors.New("dummy"); err != nil; lvs = append(lvs, magicString) {
-		m, err = prometheus.NewConstMetric(desc, prometheus.UntypedValue, 0, lvs...)
-	}
-
-	// Write out the metric into a proto message and look at the labels.
-	// If the value is not the magicString, it is a constLabel, which doesn't interest us.
-	// If the label is curried, it doesn't interest us.
-	// In all other cases, only "code" or "method" is allowed.
-	if err := m.Write(&pm); err != nil {
-		panic("error checking metric for labels")
-	}
-	for _, label := range pm.Label {
-		name, value := label.GetName(), label.GetValue()
-		if value != magicString || isLabelCurried(c, name) {
-			continue
-		}
-		switch name {
-		case "code":
-			code = true
-		case "method":
-			method = true
-		default:
-			panic("metric partitioned with non-supported labels")
-		}
-	}
-	return
-}
-
-func isLabelCurried(c prometheus.Collector, label string) bool {
-	// This is even hackier than the label test above.
-	// We essentially try to curry again and see if it works.
-	// But for that, we need to type-convert to the two
-	// types we use here, ObserverVec or *CounterVec.
-	switch v := c.(type) {
-	case *prometheus.CounterVec:
-		if _, err := v.CurryWith(prometheus.Labels{label: "dummy"}); err == nil {
-			return false
-		}
-	case prometheus.ObserverVec:
-		if _, err := v.CurryWith(prometheus.Labels{label: "dummy"}); err == nil {
-			return false
-		}
-	default:
-		panic("unsupported metric vec type")
-	}
-	return true
-}
-
-// emptyLabels is a one-time allocation for non-partitioned metrics to avoid
-// unnecessary allocations on each request.
-var emptyLabels = prometheus.Labels{}
-
-func labels(code, method bool, reqMethod string, status int) prometheus.Labels {
-	if !(code || method) {
-		return emptyLabels
-	}
-	labels := prometheus.Labels{}
-
-	if code {
-		labels["code"] = sanitizeCode(status)
-	}
-	if method {
-		labels["method"] = sanitizeMethod(reqMethod)
-	}
-
-	return labels
-}
-
-func computeApproximateRequestSize(r *http.Request) int {
-	s := 0
-	if r.URL != nil {
-		s += len(r.URL.String())
-	}
-
-	s += len(r.Method)
-	s += len(r.Proto)
-	for name, values := range r.Header {
-		s += len(name)
-		for _, value := range values {
-			s += len(value)
-		}
-	}
-	s += len(r.Host)
-
-	// N.B. r.Form and r.MultipartForm are assumed to be included in r.URL.
-
-	if r.ContentLength != -1 {
-		s += int(r.ContentLength)
-	}
-	return s
-}
-
-func sanitizeMethod(m string) string {
-	switch m {
-	case "GET", "get":
-		return "get"
-	case "PUT", "put":
-		return "put"
-	case "HEAD", "head":
-		return "head"
-	case "POST", "post":
-		return "post"
-	case "DELETE", "delete":
-		return "delete"
-	case "CONNECT", "connect":
-		return "connect"
-	case "OPTIONS", "options":
-		return "options"
-	case "NOTIFY", "notify":
-		return "notify"
-	default:
-		return strings.ToLower(m)
-	}
-}
-
-// If the wrapped http.Handler has not set a status code, i.e. the value is
-// currently 0, santizeCode will return 200, for consistency with behavior in
-// the stdlib.
-func sanitizeCode(s int) string {
-	switch s {
-	case 100:
-		return "100"
-	case 101:
-		return "101"
-
-	case 200, 0:
-		return "200"
-	case 201:
-		return "201"
-	case 202:
-		return "202"
-	case 203:
-		return "203"
-	case 204:
-		return "204"
-	case 205:
-		return "205"
-	case 206:
-		return "206"
-
-	case 300:
-		return "300"
-	case 301:
-		return "301"
-	case 302:
-		return "302"
-	case 304:
-		return "304"
-	case 305:
-		return "305"
-	case 307:
-		return "307"
-
-	case 400:
-		return "400"
-	case 401:
-		return "401"
-	case 402:
-		return "402"
-	case 403:
-		return "403"
-	case 404:
-		return "404"
-	case 405:
-		return "405"
-	case 406:
-		return "406"
-	case 407:
-		return "407"
-	case 408:
-		return "408"
-	case 409:
-		return "409"
-	case 410:
-		return "410"
-	case 411:
-		return "411"
-	case 412:
-		return "412"
-	case 413:
-		return "413"
-	case 414:
-		return "414"
-	case 415:
-		return "415"
-	case 416:
-		return "416"
-	case 417:
-		return "417"
-	case 418:
-		return "418"
-
-	case 500:
-		return "500"
-	case 501:
-		return "501"
-	case 502:
-		return "502"
-	case 503:
-		return "503"
-	case 504:
-		return "504"
-	case 505:
-		return "505"
-
-	case 428:
-		return "428"
-	case 429:
-		return "429"
-	case 431:
-		return "431"
-	case 511:
-		return "511"
-
-	default:
-		return strconv.Itoa(s)
-	}
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/registry.go b/vendor/github.com/prometheus/client_golang/prometheus/registry.go
deleted file mode 100644
index 896838f..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/registry.go
+++ /dev/null
@@ -1,941 +0,0 @@
-// Copyright 2014 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"bytes"
-	"fmt"
-	"os"
-	"runtime"
-	"sort"
-	"strings"
-	"sync"
-	"unicode/utf8"
-
-	"github.com/golang/protobuf/proto"
-
-	dto "github.com/prometheus/client_model/go"
-)
-
-const (
-	// Capacity for the channel to collect metrics and descriptors.
-	capMetricChan = 1000
-	capDescChan   = 10
-)
-
-// DefaultRegisterer and DefaultGatherer are the implementations of the
-// Registerer and Gatherer interface a number of convenience functions in this
-// package act on. Initially, both variables point to the same Registry, which
-// has a process collector (currently on Linux only, see NewProcessCollector)
-// and a Go collector (see NewGoCollector, in particular the note about
-// stop-the-world implication with Go versions older than 1.9) already
-// registered. This approach to keep default instances as global state mirrors
-// the approach of other packages in the Go standard library. Note that there
-// are caveats. Change the variables with caution and only if you understand the
-// consequences. Users who want to avoid global state altogether should not use
-// the convenience functions and act on custom instances instead.
-var (
-	defaultRegistry              = NewRegistry()
-	DefaultRegisterer Registerer = defaultRegistry
-	DefaultGatherer   Gatherer   = defaultRegistry
-)
-
-func init() {
-	MustRegister(NewProcessCollector(os.Getpid(), ""))
-	MustRegister(NewGoCollector())
-}
-
-// NewRegistry creates a new vanilla Registry without any Collectors
-// pre-registered.
-func NewRegistry() *Registry {
-	return &Registry{
-		collectorsByID:  map[uint64]Collector{},
-		descIDs:         map[uint64]struct{}{},
-		dimHashesByName: map[string]uint64{},
-	}
-}
-
-// NewPedanticRegistry returns a registry that checks during collection if each
-// collected Metric is consistent with its reported Desc, and if the Desc has
-// actually been registered with the registry. Unchecked Collectors (those whose
-// Describe methed does not yield any descriptors) are excluded from the check.
-//
-// Usually, a Registry will be happy as long as the union of all collected
-// Metrics is consistent and valid even if some metrics are not consistent with
-// their own Desc or a Desc provided by their registered Collector. Well-behaved
-// Collectors and Metrics will only provide consistent Descs. This Registry is
-// useful to test the implementation of Collectors and Metrics.
-func NewPedanticRegistry() *Registry {
-	r := NewRegistry()
-	r.pedanticChecksEnabled = true
-	return r
-}
-
-// Registerer is the interface for the part of a registry in charge of
-// registering and unregistering. Users of custom registries should use
-// Registerer as type for registration purposes (rather than the Registry type
-// directly). In that way, they are free to use custom Registerer implementation
-// (e.g. for testing purposes).
-type Registerer interface {
-	// Register registers a new Collector to be included in metrics
-	// collection. It returns an error if the descriptors provided by the
-	// Collector are invalid or if they — in combination with descriptors of
-	// already registered Collectors — do not fulfill the consistency and
-	// uniqueness criteria described in the documentation of metric.Desc.
-	//
-	// If the provided Collector is equal to a Collector already registered
-	// (which includes the case of re-registering the same Collector), the
-	// returned error is an instance of AlreadyRegisteredError, which
-	// contains the previously registered Collector.
-	//
-	// A Collector whose Describe method does not yield any Desc is treated
-	// as unchecked. Registration will always succeed. No check for
-	// re-registering (see previous paragraph) is performed. Thus, the
-	// caller is responsible for not double-registering the same unchecked
-	// Collector, and for providing a Collector that will not cause
-	// inconsistent metrics on collection. (This would lead to scrape
-	// errors.)
-	//
-	// It is in general not safe to register the same Collector multiple
-	// times concurrently.
-	Register(Collector) error
-	// MustRegister works like Register but registers any number of
-	// Collectors and panics upon the first registration that causes an
-	// error.
-	MustRegister(...Collector)
-	// Unregister unregisters the Collector that equals the Collector passed
-	// in as an argument.  (Two Collectors are considered equal if their
-	// Describe method yields the same set of descriptors.) The function
-	// returns whether a Collector was unregistered. Note that an unchecked
-	// Collector cannot be unregistered (as its Describe method does not
-	// yield any descriptor).
-	//
-	// Note that even after unregistering, it will not be possible to
-	// register a new Collector that is inconsistent with the unregistered
-	// Collector, e.g. a Collector collecting metrics with the same name but
-	// a different help string. The rationale here is that the same registry
-	// instance must only collect consistent metrics throughout its
-	// lifetime.
-	Unregister(Collector) bool
-}
-
-// Gatherer is the interface for the part of a registry in charge of gathering
-// the collected metrics into a number of MetricFamilies. The Gatherer interface
-// comes with the same general implication as described for the Registerer
-// interface.
-type Gatherer interface {
-	// Gather calls the Collect method of the registered Collectors and then
-	// gathers the collected metrics into a lexicographically sorted slice
-	// of uniquely named MetricFamily protobufs. Gather ensures that the
-	// returned slice is valid and self-consistent so that it can be used
-	// for valid exposition. As an exception to the strict consistency
-	// requirements described for metric.Desc, Gather will tolerate
-	// different sets of label names for metrics of the same metric family.
-	//
-	// Even if an error occurs, Gather attempts to gather as many metrics as
-	// possible. Hence, if a non-nil error is returned, the returned
-	// MetricFamily slice could be nil (in case of a fatal error that
-	// prevented any meaningful metric collection) or contain a number of
-	// MetricFamily protobufs, some of which might be incomplete, and some
-	// might be missing altogether. The returned error (which might be a
-	// MultiError) explains the details. Note that this is mostly useful for
-	// debugging purposes. If the gathered protobufs are to be used for
-	// exposition in actual monitoring, it is almost always better to not
-	// expose an incomplete result and instead disregard the returned
-	// MetricFamily protobufs in case the returned error is non-nil.
-	Gather() ([]*dto.MetricFamily, error)
-}
-
-// Register registers the provided Collector with the DefaultRegisterer.
-//
-// Register is a shortcut for DefaultRegisterer.Register(c). See there for more
-// details.
-func Register(c Collector) error {
-	return DefaultRegisterer.Register(c)
-}
-
-// MustRegister registers the provided Collectors with the DefaultRegisterer and
-// panics if any error occurs.
-//
-// MustRegister is a shortcut for DefaultRegisterer.MustRegister(cs...). See
-// there for more details.
-func MustRegister(cs ...Collector) {
-	DefaultRegisterer.MustRegister(cs...)
-}
-
-// Unregister removes the registration of the provided Collector from the
-// DefaultRegisterer.
-//
-// Unregister is a shortcut for DefaultRegisterer.Unregister(c). See there for
-// more details.
-func Unregister(c Collector) bool {
-	return DefaultRegisterer.Unregister(c)
-}
-
-// GathererFunc turns a function into a Gatherer.
-type GathererFunc func() ([]*dto.MetricFamily, error)
-
-// Gather implements Gatherer.
-func (gf GathererFunc) Gather() ([]*dto.MetricFamily, error) {
-	return gf()
-}
-
-// AlreadyRegisteredError is returned by the Register method if the Collector to
-// be registered has already been registered before, or a different Collector
-// that collects the same metrics has been registered before. Registration fails
-// in that case, but you can detect from the kind of error what has
-// happened. The error contains fields for the existing Collector and the
-// (rejected) new Collector that equals the existing one. This can be used to
-// find out if an equal Collector has been registered before and switch over to
-// using the old one, as demonstrated in the example.
-type AlreadyRegisteredError struct {
-	ExistingCollector, NewCollector Collector
-}
-
-func (err AlreadyRegisteredError) Error() string {
-	return "duplicate metrics collector registration attempted"
-}
-
-// MultiError is a slice of errors implementing the error interface. It is used
-// by a Gatherer to report multiple errors during MetricFamily gathering.
-type MultiError []error
-
-func (errs MultiError) Error() string {
-	if len(errs) == 0 {
-		return ""
-	}
-	buf := &bytes.Buffer{}
-	fmt.Fprintf(buf, "%d error(s) occurred:", len(errs))
-	for _, err := range errs {
-		fmt.Fprintf(buf, "\n* %s", err)
-	}
-	return buf.String()
-}
-
-// Append appends the provided error if it is not nil.
-func (errs *MultiError) Append(err error) {
-	if err != nil {
-		*errs = append(*errs, err)
-	}
-}
-
-// MaybeUnwrap returns nil if len(errs) is 0. It returns the first and only
-// contained error as error if len(errs is 1). In all other cases, it returns
-// the MultiError directly. This is helpful for returning a MultiError in a way
-// that only uses the MultiError if needed.
-func (errs MultiError) MaybeUnwrap() error {
-	switch len(errs) {
-	case 0:
-		return nil
-	case 1:
-		return errs[0]
-	default:
-		return errs
-	}
-}
-
-// Registry registers Prometheus collectors, collects their metrics, and gathers
-// them into MetricFamilies for exposition. It implements both Registerer and
-// Gatherer. The zero value is not usable. Create instances with NewRegistry or
-// NewPedanticRegistry.
-type Registry struct {
-	mtx                   sync.RWMutex
-	collectorsByID        map[uint64]Collector // ID is a hash of the descIDs.
-	descIDs               map[uint64]struct{}
-	dimHashesByName       map[string]uint64
-	uncheckedCollectors   []Collector
-	pedanticChecksEnabled bool
-}
-
-// Register implements Registerer.
-func (r *Registry) Register(c Collector) error {
-	var (
-		descChan           = make(chan *Desc, capDescChan)
-		newDescIDs         = map[uint64]struct{}{}
-		newDimHashesByName = map[string]uint64{}
-		collectorID        uint64 // Just a sum of all desc IDs.
-		duplicateDescErr   error
-	)
-	go func() {
-		c.Describe(descChan)
-		close(descChan)
-	}()
-	r.mtx.Lock()
-	defer r.mtx.Unlock()
-	// Conduct various tests...
-	for desc := range descChan {
-
-		// Is the descriptor valid at all?
-		if desc.err != nil {
-			return fmt.Errorf("descriptor %s is invalid: %s", desc, desc.err)
-		}
-
-		// Is the descID unique?
-		// (In other words: Is the fqName + constLabel combination unique?)
-		if _, exists := r.descIDs[desc.id]; exists {
-			duplicateDescErr = fmt.Errorf("descriptor %s already exists with the same fully-qualified name and const label values", desc)
-		}
-		// If it is not a duplicate desc in this collector, add it to
-		// the collectorID.  (We allow duplicate descs within the same
-		// collector, but their existence must be a no-op.)
-		if _, exists := newDescIDs[desc.id]; !exists {
-			newDescIDs[desc.id] = struct{}{}
-			collectorID += desc.id
-		}
-
-		// Are all the label names and the help string consistent with
-		// previous descriptors of the same name?
-		// First check existing descriptors...
-		if dimHash, exists := r.dimHashesByName[desc.fqName]; exists {
-			if dimHash != desc.dimHash {
-				return fmt.Errorf("a previously registered descriptor with the same fully-qualified name as %s has different label names or a different help string", desc)
-			}
-		} else {
-			// ...then check the new descriptors already seen.
-			if dimHash, exists := newDimHashesByName[desc.fqName]; exists {
-				if dimHash != desc.dimHash {
-					return fmt.Errorf("descriptors reported by collector have inconsistent label names or help strings for the same fully-qualified name, offender is %s", desc)
-				}
-			} else {
-				newDimHashesByName[desc.fqName] = desc.dimHash
-			}
-		}
-	}
-	// A Collector yielding no Desc at all is considered unchecked.
-	if len(newDescIDs) == 0 {
-		r.uncheckedCollectors = append(r.uncheckedCollectors, c)
-		return nil
-	}
-	if existing, exists := r.collectorsByID[collectorID]; exists {
-		return AlreadyRegisteredError{
-			ExistingCollector: existing,
-			NewCollector:      c,
-		}
-	}
-	// If the collectorID is new, but at least one of the descs existed
-	// before, we are in trouble.
-	if duplicateDescErr != nil {
-		return duplicateDescErr
-	}
-
-	// Only after all tests have passed, actually register.
-	r.collectorsByID[collectorID] = c
-	for hash := range newDescIDs {
-		r.descIDs[hash] = struct{}{}
-	}
-	for name, dimHash := range newDimHashesByName {
-		r.dimHashesByName[name] = dimHash
-	}
-	return nil
-}
-
-// Unregister implements Registerer.
-func (r *Registry) Unregister(c Collector) bool {
-	var (
-		descChan    = make(chan *Desc, capDescChan)
-		descIDs     = map[uint64]struct{}{}
-		collectorID uint64 // Just a sum of the desc IDs.
-	)
-	go func() {
-		c.Describe(descChan)
-		close(descChan)
-	}()
-	for desc := range descChan {
-		if _, exists := descIDs[desc.id]; !exists {
-			collectorID += desc.id
-			descIDs[desc.id] = struct{}{}
-		}
-	}
-
-	r.mtx.RLock()
-	if _, exists := r.collectorsByID[collectorID]; !exists {
-		r.mtx.RUnlock()
-		return false
-	}
-	r.mtx.RUnlock()
-
-	r.mtx.Lock()
-	defer r.mtx.Unlock()
-
-	delete(r.collectorsByID, collectorID)
-	for id := range descIDs {
-		delete(r.descIDs, id)
-	}
-	// dimHashesByName is left untouched as those must be consistent
-	// throughout the lifetime of a program.
-	return true
-}
-
-// MustRegister implements Registerer.
-func (r *Registry) MustRegister(cs ...Collector) {
-	for _, c := range cs {
-		if err := r.Register(c); err != nil {
-			panic(err)
-		}
-	}
-}
-
-// Gather implements Gatherer.
-func (r *Registry) Gather() ([]*dto.MetricFamily, error) {
-	var (
-		checkedMetricChan   = make(chan Metric, capMetricChan)
-		uncheckedMetricChan = make(chan Metric, capMetricChan)
-		metricHashes        = map[uint64]struct{}{}
-		wg                  sync.WaitGroup
-		errs                MultiError          // The collected errors to return in the end.
-		registeredDescIDs   map[uint64]struct{} // Only used for pedantic checks
-	)
-
-	r.mtx.RLock()
-	goroutineBudget := len(r.collectorsByID) + len(r.uncheckedCollectors)
-	metricFamiliesByName := make(map[string]*dto.MetricFamily, len(r.dimHashesByName))
-	checkedCollectors := make(chan Collector, len(r.collectorsByID))
-	uncheckedCollectors := make(chan Collector, len(r.uncheckedCollectors))
-	for _, collector := range r.collectorsByID {
-		checkedCollectors <- collector
-	}
-	for _, collector := range r.uncheckedCollectors {
-		uncheckedCollectors <- collector
-	}
-	// In case pedantic checks are enabled, we have to copy the map before
-	// giving up the RLock.
-	if r.pedanticChecksEnabled {
-		registeredDescIDs = make(map[uint64]struct{}, len(r.descIDs))
-		for id := range r.descIDs {
-			registeredDescIDs[id] = struct{}{}
-		}
-	}
-	r.mtx.RUnlock()
-
-	wg.Add(goroutineBudget)
-
-	collectWorker := func() {
-		for {
-			select {
-			case collector := <-checkedCollectors:
-				collector.Collect(checkedMetricChan)
-			case collector := <-uncheckedCollectors:
-				collector.Collect(uncheckedMetricChan)
-			default:
-				return
-			}
-			wg.Done()
-		}
-	}
-
-	// Start the first worker now to make sure at least one is running.
-	go collectWorker()
-	goroutineBudget--
-
-	// Close checkedMetricChan and uncheckedMetricChan once all collectors
-	// are collected.
-	go func() {
-		wg.Wait()
-		close(checkedMetricChan)
-		close(uncheckedMetricChan)
-	}()
-
-	// Drain checkedMetricChan and uncheckedMetricChan in case of premature return.
-	defer func() {
-		if checkedMetricChan != nil {
-			for range checkedMetricChan {
-			}
-		}
-		if uncheckedMetricChan != nil {
-			for range uncheckedMetricChan {
-			}
-		}
-	}()
-
-	// Copy the channel references so we can nil them out later to remove
-	// them from the select statements below.
-	cmc := checkedMetricChan
-	umc := uncheckedMetricChan
-
-	for {
-		select {
-		case metric, ok := <-cmc:
-			if !ok {
-				cmc = nil
-				break
-			}
-			errs.Append(processMetric(
-				metric, metricFamiliesByName,
-				metricHashes,
-				registeredDescIDs,
-			))
-		case metric, ok := <-umc:
-			if !ok {
-				umc = nil
-				break
-			}
-			errs.Append(processMetric(
-				metric, metricFamiliesByName,
-				metricHashes,
-				nil,
-			))
-		default:
-			if goroutineBudget <= 0 || len(checkedCollectors)+len(uncheckedCollectors) == 0 {
-				// All collectors are already being worked on or
-				// we have already as many goroutines started as
-				// there are collectors. Do the same as above,
-				// just without the default.
-				select {
-				case metric, ok := <-cmc:
-					if !ok {
-						cmc = nil
-						break
-					}
-					errs.Append(processMetric(
-						metric, metricFamiliesByName,
-						metricHashes,
-						registeredDescIDs,
-					))
-				case metric, ok := <-umc:
-					if !ok {
-						umc = nil
-						break
-					}
-					errs.Append(processMetric(
-						metric, metricFamiliesByName,
-						metricHashes,
-						nil,
-					))
-				}
-				break
-			}
-			// Start more workers.
-			go collectWorker()
-			goroutineBudget--
-			runtime.Gosched()
-		}
-		// Once both checkedMetricChan and uncheckdMetricChan are closed
-		// and drained, the contraption above will nil out cmc and umc,
-		// and then we can leave the collect loop here.
-		if cmc == nil && umc == nil {
-			break
-		}
-	}
-	return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
-}
-
-// processMetric is an internal helper method only used by the Gather method.
-func processMetric(
-	metric Metric,
-	metricFamiliesByName map[string]*dto.MetricFamily,
-	metricHashes map[uint64]struct{},
-	registeredDescIDs map[uint64]struct{},
-) error {
-	desc := metric.Desc()
-	dtoMetric := &dto.Metric{}
-	if err := metric.Write(dtoMetric); err != nil {
-		return fmt.Errorf("error collecting metric %v: %s", desc, err)
-	}
-	metricFamily, ok := metricFamiliesByName[desc.fqName]
-	if ok { // Existing name.
-		if metricFamily.GetHelp() != desc.help {
-			return fmt.Errorf(
-				"collected metric %s %s has help %q but should have %q",
-				desc.fqName, dtoMetric, desc.help, metricFamily.GetHelp(),
-			)
-		}
-		// TODO(beorn7): Simplify switch once Desc has type.
-		switch metricFamily.GetType() {
-		case dto.MetricType_COUNTER:
-			if dtoMetric.Counter == nil {
-				return fmt.Errorf(
-					"collected metric %s %s should be a Counter",
-					desc.fqName, dtoMetric,
-				)
-			}
-		case dto.MetricType_GAUGE:
-			if dtoMetric.Gauge == nil {
-				return fmt.Errorf(
-					"collected metric %s %s should be a Gauge",
-					desc.fqName, dtoMetric,
-				)
-			}
-		case dto.MetricType_SUMMARY:
-			if dtoMetric.Summary == nil {
-				return fmt.Errorf(
-					"collected metric %s %s should be a Summary",
-					desc.fqName, dtoMetric,
-				)
-			}
-		case dto.MetricType_UNTYPED:
-			if dtoMetric.Untyped == nil {
-				return fmt.Errorf(
-					"collected metric %s %s should be Untyped",
-					desc.fqName, dtoMetric,
-				)
-			}
-		case dto.MetricType_HISTOGRAM:
-			if dtoMetric.Histogram == nil {
-				return fmt.Errorf(
-					"collected metric %s %s should be a Histogram",
-					desc.fqName, dtoMetric,
-				)
-			}
-		default:
-			panic("encountered MetricFamily with invalid type")
-		}
-	} else { // New name.
-		metricFamily = &dto.MetricFamily{}
-		metricFamily.Name = proto.String(desc.fqName)
-		metricFamily.Help = proto.String(desc.help)
-		// TODO(beorn7): Simplify switch once Desc has type.
-		switch {
-		case dtoMetric.Gauge != nil:
-			metricFamily.Type = dto.MetricType_GAUGE.Enum()
-		case dtoMetric.Counter != nil:
-			metricFamily.Type = dto.MetricType_COUNTER.Enum()
-		case dtoMetric.Summary != nil:
-			metricFamily.Type = dto.MetricType_SUMMARY.Enum()
-		case dtoMetric.Untyped != nil:
-			metricFamily.Type = dto.MetricType_UNTYPED.Enum()
-		case dtoMetric.Histogram != nil:
-			metricFamily.Type = dto.MetricType_HISTOGRAM.Enum()
-		default:
-			return fmt.Errorf("empty metric collected: %s", dtoMetric)
-		}
-		if err := checkSuffixCollisions(metricFamily, metricFamiliesByName); err != nil {
-			return err
-		}
-		metricFamiliesByName[desc.fqName] = metricFamily
-	}
-	if err := checkMetricConsistency(metricFamily, dtoMetric, metricHashes); err != nil {
-		return err
-	}
-	if registeredDescIDs != nil {
-		// Is the desc registered at all?
-		if _, exist := registeredDescIDs[desc.id]; !exist {
-			return fmt.Errorf(
-				"collected metric %s %s with unregistered descriptor %s",
-				metricFamily.GetName(), dtoMetric, desc,
-			)
-		}
-		if err := checkDescConsistency(metricFamily, dtoMetric, desc); err != nil {
-			return err
-		}
-	}
-	metricFamily.Metric = append(metricFamily.Metric, dtoMetric)
-	return nil
-}
-
-// Gatherers is a slice of Gatherer instances that implements the Gatherer
-// interface itself. Its Gather method calls Gather on all Gatherers in the
-// slice in order and returns the merged results. Errors returned from the
-// Gather calles are all returned in a flattened MultiError. Duplicate and
-// inconsistent Metrics are skipped (first occurrence in slice order wins) and
-// reported in the returned error.
-//
-// Gatherers can be used to merge the Gather results from multiple
-// Registries. It also provides a way to directly inject existing MetricFamily
-// protobufs into the gathering by creating a custom Gatherer with a Gather
-// method that simply returns the existing MetricFamily protobufs. Note that no
-// registration is involved (in contrast to Collector registration), so
-// obviously registration-time checks cannot happen. Any inconsistencies between
-// the gathered MetricFamilies are reported as errors by the Gather method, and
-// inconsistent Metrics are dropped. Invalid parts of the MetricFamilies
-// (e.g. syntactically invalid metric or label names) will go undetected.
-type Gatherers []Gatherer
-
-// Gather implements Gatherer.
-func (gs Gatherers) Gather() ([]*dto.MetricFamily, error) {
-	var (
-		metricFamiliesByName = map[string]*dto.MetricFamily{}
-		metricHashes         = map[uint64]struct{}{}
-		errs                 MultiError // The collected errors to return in the end.
-	)
-
-	for i, g := range gs {
-		mfs, err := g.Gather()
-		if err != nil {
-			if multiErr, ok := err.(MultiError); ok {
-				for _, err := range multiErr {
-					errs = append(errs, fmt.Errorf("[from Gatherer #%d] %s", i+1, err))
-				}
-			} else {
-				errs = append(errs, fmt.Errorf("[from Gatherer #%d] %s", i+1, err))
-			}
-		}
-		for _, mf := range mfs {
-			existingMF, exists := metricFamiliesByName[mf.GetName()]
-			if exists {
-				if existingMF.GetHelp() != mf.GetHelp() {
-					errs = append(errs, fmt.Errorf(
-						"gathered metric family %s has help %q but should have %q",
-						mf.GetName(), mf.GetHelp(), existingMF.GetHelp(),
-					))
-					continue
-				}
-				if existingMF.GetType() != mf.GetType() {
-					errs = append(errs, fmt.Errorf(
-						"gathered metric family %s has type %s but should have %s",
-						mf.GetName(), mf.GetType(), existingMF.GetType(),
-					))
-					continue
-				}
-			} else {
-				existingMF = &dto.MetricFamily{}
-				existingMF.Name = mf.Name
-				existingMF.Help = mf.Help
-				existingMF.Type = mf.Type
-				if err := checkSuffixCollisions(existingMF, metricFamiliesByName); err != nil {
-					errs = append(errs, err)
-					continue
-				}
-				metricFamiliesByName[mf.GetName()] = existingMF
-			}
-			for _, m := range mf.Metric {
-				if err := checkMetricConsistency(existingMF, m, metricHashes); err != nil {
-					errs = append(errs, err)
-					continue
-				}
-				existingMF.Metric = append(existingMF.Metric, m)
-			}
-		}
-	}
-	return normalizeMetricFamilies(metricFamiliesByName), errs.MaybeUnwrap()
-}
-
-// metricSorter is a sortable slice of *dto.Metric.
-type metricSorter []*dto.Metric
-
-func (s metricSorter) Len() int {
-	return len(s)
-}
-
-func (s metricSorter) Swap(i, j int) {
-	s[i], s[j] = s[j], s[i]
-}
-
-func (s metricSorter) Less(i, j int) bool {
-	if len(s[i].Label) != len(s[j].Label) {
-		// This should not happen. The metrics are
-		// inconsistent. However, we have to deal with the fact, as
-		// people might use custom collectors or metric family injection
-		// to create inconsistent metrics. So let's simply compare the
-		// number of labels in this case. That will still yield
-		// reproducible sorting.
-		return len(s[i].Label) < len(s[j].Label)
-	}
-	for n, lp := range s[i].Label {
-		vi := lp.GetValue()
-		vj := s[j].Label[n].GetValue()
-		if vi != vj {
-			return vi < vj
-		}
-	}
-
-	// We should never arrive here. Multiple metrics with the same
-	// label set in the same scrape will lead to undefined ingestion
-	// behavior. However, as above, we have to provide stable sorting
-	// here, even for inconsistent metrics. So sort equal metrics
-	// by their timestamp, with missing timestamps (implying "now")
-	// coming last.
-	if s[i].TimestampMs == nil {
-		return false
-	}
-	if s[j].TimestampMs == nil {
-		return true
-	}
-	return s[i].GetTimestampMs() < s[j].GetTimestampMs()
-}
-
-// normalizeMetricFamilies returns a MetricFamily slice with empty
-// MetricFamilies pruned and the remaining MetricFamilies sorted by name within
-// the slice, with the contained Metrics sorted within each MetricFamily.
-func normalizeMetricFamilies(metricFamiliesByName map[string]*dto.MetricFamily) []*dto.MetricFamily {
-	for _, mf := range metricFamiliesByName {
-		sort.Sort(metricSorter(mf.Metric))
-	}
-	names := make([]string, 0, len(metricFamiliesByName))
-	for name, mf := range metricFamiliesByName {
-		if len(mf.Metric) > 0 {
-			names = append(names, name)
-		}
-	}
-	sort.Strings(names)
-	result := make([]*dto.MetricFamily, 0, len(names))
-	for _, name := range names {
-		result = append(result, metricFamiliesByName[name])
-	}
-	return result
-}
-
-// checkSuffixCollisions checks for collisions with the “magic” suffixes the
-// Prometheus text format and the internal metric representation of the
-// Prometheus server add while flattening Summaries and Histograms.
-func checkSuffixCollisions(mf *dto.MetricFamily, mfs map[string]*dto.MetricFamily) error {
-	var (
-		newName              = mf.GetName()
-		newType              = mf.GetType()
-		newNameWithoutSuffix = ""
-	)
-	switch {
-	case strings.HasSuffix(newName, "_count"):
-		newNameWithoutSuffix = newName[:len(newName)-6]
-	case strings.HasSuffix(newName, "_sum"):
-		newNameWithoutSuffix = newName[:len(newName)-4]
-	case strings.HasSuffix(newName, "_bucket"):
-		newNameWithoutSuffix = newName[:len(newName)-7]
-	}
-	if newNameWithoutSuffix != "" {
-		if existingMF, ok := mfs[newNameWithoutSuffix]; ok {
-			switch existingMF.GetType() {
-			case dto.MetricType_SUMMARY:
-				if !strings.HasSuffix(newName, "_bucket") {
-					return fmt.Errorf(
-						"collected metric named %q collides with previously collected summary named %q",
-						newName, newNameWithoutSuffix,
-					)
-				}
-			case dto.MetricType_HISTOGRAM:
-				return fmt.Errorf(
-					"collected metric named %q collides with previously collected histogram named %q",
-					newName, newNameWithoutSuffix,
-				)
-			}
-		}
-	}
-	if newType == dto.MetricType_SUMMARY || newType == dto.MetricType_HISTOGRAM {
-		if _, ok := mfs[newName+"_count"]; ok {
-			return fmt.Errorf(
-				"collected histogram or summary named %q collides with previously collected metric named %q",
-				newName, newName+"_count",
-			)
-		}
-		if _, ok := mfs[newName+"_sum"]; ok {
-			return fmt.Errorf(
-				"collected histogram or summary named %q collides with previously collected metric named %q",
-				newName, newName+"_sum",
-			)
-		}
-	}
-	if newType == dto.MetricType_HISTOGRAM {
-		if _, ok := mfs[newName+"_bucket"]; ok {
-			return fmt.Errorf(
-				"collected histogram named %q collides with previously collected metric named %q",
-				newName, newName+"_bucket",
-			)
-		}
-	}
-	return nil
-}
-
-// checkMetricConsistency checks if the provided Metric is consistent with the
-// provided MetricFamily. It also hashes the Metric labels and the MetricFamily
-// name. If the resulting hash is already in the provided metricHashes, an error
-// is returned. If not, it is added to metricHashes.
-func checkMetricConsistency(
-	metricFamily *dto.MetricFamily,
-	dtoMetric *dto.Metric,
-	metricHashes map[uint64]struct{},
-) error {
-	// Type consistency with metric family.
-	if metricFamily.GetType() == dto.MetricType_GAUGE && dtoMetric.Gauge == nil ||
-		metricFamily.GetType() == dto.MetricType_COUNTER && dtoMetric.Counter == nil ||
-		metricFamily.GetType() == dto.MetricType_SUMMARY && dtoMetric.Summary == nil ||
-		metricFamily.GetType() == dto.MetricType_HISTOGRAM && dtoMetric.Histogram == nil ||
-		metricFamily.GetType() == dto.MetricType_UNTYPED && dtoMetric.Untyped == nil {
-		return fmt.Errorf(
-			"collected metric %q { %s} is not a %s",
-			metricFamily.GetName(), dtoMetric, metricFamily.GetType(),
-		)
-	}
-
-	for _, labelPair := range dtoMetric.GetLabel() {
-		if !checkLabelName(labelPair.GetName()) {
-			return fmt.Errorf(
-				"collected metric %q { %s} has a label with an invalid name: %s",
-				metricFamily.GetName(), dtoMetric, labelPair.GetName(),
-			)
-		}
-		if dtoMetric.Summary != nil && labelPair.GetName() == quantileLabel {
-			return fmt.Errorf(
-				"collected metric %q { %s} must not have an explicit %q label",
-				metricFamily.GetName(), dtoMetric, quantileLabel,
-			)
-		}
-		if !utf8.ValidString(labelPair.GetValue()) {
-			return fmt.Errorf(
-				"collected metric %q { %s} has a label named %q whose value is not utf8: %#v",
-				metricFamily.GetName(), dtoMetric, labelPair.GetName(), labelPair.GetValue())
-		}
-	}
-
-	// Is the metric unique (i.e. no other metric with the same name and the same labels)?
-	h := hashNew()
-	h = hashAdd(h, metricFamily.GetName())
-	h = hashAddByte(h, separatorByte)
-	// Make sure label pairs are sorted. We depend on it for the consistency
-	// check.
-	sort.Sort(LabelPairSorter(dtoMetric.Label))
-	for _, lp := range dtoMetric.Label {
-		h = hashAdd(h, lp.GetName())
-		h = hashAddByte(h, separatorByte)
-		h = hashAdd(h, lp.GetValue())
-		h = hashAddByte(h, separatorByte)
-	}
-	if _, exists := metricHashes[h]; exists {
-		return fmt.Errorf(
-			"collected metric %q { %s} was collected before with the same name and label values",
-			metricFamily.GetName(), dtoMetric,
-		)
-	}
-	metricHashes[h] = struct{}{}
-	return nil
-}
-
-func checkDescConsistency(
-	metricFamily *dto.MetricFamily,
-	dtoMetric *dto.Metric,
-	desc *Desc,
-) error {
-	// Desc help consistency with metric family help.
-	if metricFamily.GetHelp() != desc.help {
-		return fmt.Errorf(
-			"collected metric %s %s has help %q but should have %q",
-			metricFamily.GetName(), dtoMetric, metricFamily.GetHelp(), desc.help,
-		)
-	}
-
-	// Is the desc consistent with the content of the metric?
-	lpsFromDesc := make([]*dto.LabelPair, 0, len(dtoMetric.Label))
-	lpsFromDesc = append(lpsFromDesc, desc.constLabelPairs...)
-	for _, l := range desc.variableLabels {
-		lpsFromDesc = append(lpsFromDesc, &dto.LabelPair{
-			Name: proto.String(l),
-		})
-	}
-	if len(lpsFromDesc) != len(dtoMetric.Label) {
-		return fmt.Errorf(
-			"labels in collected metric %s %s are inconsistent with descriptor %s",
-			metricFamily.GetName(), dtoMetric, desc,
-		)
-	}
-	sort.Sort(LabelPairSorter(lpsFromDesc))
-	for i, lpFromDesc := range lpsFromDesc {
-		lpFromMetric := dtoMetric.Label[i]
-		if lpFromDesc.GetName() != lpFromMetric.GetName() ||
-			lpFromDesc.Value != nil && lpFromDesc.GetValue() != lpFromMetric.GetValue() {
-			return fmt.Errorf(
-				"labels in collected metric %s %s are inconsistent with descriptor %s",
-				metricFamily.GetName(), dtoMetric, desc,
-			)
-		}
-	}
-	return nil
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/summary.go b/vendor/github.com/prometheus/client_golang/prometheus/summary.go
deleted file mode 100644
index 83b403c..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/summary.go
+++ /dev/null
@@ -1,623 +0,0 @@
-// Copyright 2014 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"fmt"
-	"math"
-	"sort"
-	"sync"
-	"time"
-
-	"github.com/beorn7/perks/quantile"
-	"github.com/golang/protobuf/proto"
-
-	dto "github.com/prometheus/client_model/go"
-)
-
-// quantileLabel is used for the label that defines the quantile in a
-// summary.
-const quantileLabel = "quantile"
-
-// A Summary captures individual observations from an event or sample stream and
-// summarizes them in a manner similar to traditional summary statistics: 1. sum
-// of observations, 2. observation count, 3. rank estimations.
-//
-// A typical use-case is the observation of request latencies. By default, a
-// Summary provides the median, the 90th and the 99th percentile of the latency
-// as rank estimations. However, the default behavior will change in the
-// upcoming v0.10 of the library. There will be no rank estiamtions at all by
-// default. For a sane transition, it is recommended to set the desired rank
-// estimations explicitly.
-//
-// Note that the rank estimations cannot be aggregated in a meaningful way with
-// the Prometheus query language (i.e. you cannot average or add them). If you
-// need aggregatable quantiles (e.g. you want the 99th percentile latency of all
-// queries served across all instances of a service), consider the Histogram
-// metric type. See the Prometheus documentation for more details.
-//
-// To create Summary instances, use NewSummary.
-type Summary interface {
-	Metric
-	Collector
-
-	// Observe adds a single observation to the summary.
-	Observe(float64)
-}
-
-// DefObjectives are the default Summary quantile values.
-//
-// Deprecated: DefObjectives will not be used as the default objectives in
-// v0.10 of the library. The default Summary will have no quantiles then.
-var (
-	DefObjectives = map[float64]float64{0.5: 0.05, 0.9: 0.01, 0.99: 0.001}
-
-	errQuantileLabelNotAllowed = fmt.Errorf(
-		"%q is not allowed as label name in summaries", quantileLabel,
-	)
-)
-
-// Default values for SummaryOpts.
-const (
-	// DefMaxAge is the default duration for which observations stay
-	// relevant.
-	DefMaxAge time.Duration = 10 * time.Minute
-	// DefAgeBuckets is the default number of buckets used to calculate the
-	// age of observations.
-	DefAgeBuckets = 5
-	// DefBufCap is the standard buffer size for collecting Summary observations.
-	DefBufCap = 500
-)
-
-// SummaryOpts bundles the options for creating a Summary metric. It is
-// mandatory to set Name and Help to a non-empty string. While all other fields
-// are optional and can safely be left at their zero value, it is recommended to
-// explicitly set the Objectives field to the desired value as the default value
-// will change in the upcoming v0.10 of the library.
-type SummaryOpts struct {
-	// Namespace, Subsystem, and Name are components of the fully-qualified
-	// name of the Summary (created by joining these components with
-	// "_"). Only Name is mandatory, the others merely help structuring the
-	// name. Note that the fully-qualified name of the Summary must be a
-	// valid Prometheus metric name.
-	Namespace string
-	Subsystem string
-	Name      string
-
-	// Help provides information about this Summary. Mandatory!
-	//
-	// Metrics with the same fully-qualified name must have the same Help
-	// string.
-	Help string
-
-	// ConstLabels are used to attach fixed labels to this metric. Metrics
-	// with the same fully-qualified name must have the same label names in
-	// their ConstLabels.
-	//
-	// Due to the way a Summary is represented in the Prometheus text format
-	// and how it is handled by the Prometheus server internally, “quantile”
-	// is an illegal label name. Construction of a Summary or SummaryVec
-	// will panic if this label name is used in ConstLabels.
-	//
-	// ConstLabels are only used rarely. In particular, do not use them to
-	// attach the same labels to all your metrics. Those use cases are
-	// better covered by target labels set by the scraping Prometheus
-	// server, or by one specific metric (e.g. a build_info or a
-	// machine_role metric). See also
-	// https://prometheus.io/docs/instrumenting/writing_exporters/#target-labels,-not-static-scraped-labels
-	ConstLabels Labels
-
-	// Objectives defines the quantile rank estimates with their respective
-	// absolute error. If Objectives[q] = e, then the value reported for q
-	// will be the φ-quantile value for some φ between q-e and q+e.  The
-	// default value is DefObjectives. It is used if Objectives is left at
-	// its zero value (i.e. nil). To create a Summary without Objectives,
-	// set it to an empty map (i.e. map[float64]float64{}).
-	//
-	// Deprecated: Note that the current value of DefObjectives is
-	// deprecated. It will be replaced by an empty map in v0.10 of the
-	// library. Please explicitly set Objectives to the desired value.
-	Objectives map[float64]float64
-
-	// MaxAge defines the duration for which an observation stays relevant
-	// for the summary. Must be positive. The default value is DefMaxAge.
-	MaxAge time.Duration
-
-	// AgeBuckets is the number of buckets used to exclude observations that
-	// are older than MaxAge from the summary. A higher number has a
-	// resource penalty, so only increase it if the higher resolution is
-	// really required. For very high observation rates, you might want to
-	// reduce the number of age buckets. With only one age bucket, you will
-	// effectively see a complete reset of the summary each time MaxAge has
-	// passed. The default value is DefAgeBuckets.
-	AgeBuckets uint32
-
-	// BufCap defines the default sample stream buffer size.  The default
-	// value of DefBufCap should suffice for most uses. If there is a need
-	// to increase the value, a multiple of 500 is recommended (because that
-	// is the internal buffer size of the underlying package
-	// "github.com/bmizerany/perks/quantile").
-	BufCap uint32
-}
-
-// Great fuck-up with the sliding-window decay algorithm... The Merge method of
-// perk/quantile is actually not working as advertised - and it might be
-// unfixable, as the underlying algorithm is apparently not capable of merging
-// summaries in the first place. To avoid using Merge, we are currently adding
-// observations to _each_ age bucket, i.e. the effort to add a sample is
-// essentially multiplied by the number of age buckets. When rotating age
-// buckets, we empty the previous head stream. On scrape time, we simply take
-// the quantiles from the head stream (no merging required). Result: More effort
-// on observation time, less effort on scrape time, which is exactly the
-// opposite of what we try to accomplish, but at least the results are correct.
-//
-// The quite elegant previous contraption to merge the age buckets efficiently
-// on scrape time (see code up commit 6b9530d72ea715f0ba612c0120e6e09fbf1d49d0)
-// can't be used anymore.
-
-// NewSummary creates a new Summary based on the provided SummaryOpts.
-func NewSummary(opts SummaryOpts) Summary {
-	return newSummary(
-		NewDesc(
-			BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
-			opts.Help,
-			nil,
-			opts.ConstLabels,
-		),
-		opts,
-	)
-}
-
-func newSummary(desc *Desc, opts SummaryOpts, labelValues ...string) Summary {
-	if len(desc.variableLabels) != len(labelValues) {
-		panic(errInconsistentCardinality)
-	}
-
-	for _, n := range desc.variableLabels {
-		if n == quantileLabel {
-			panic(errQuantileLabelNotAllowed)
-		}
-	}
-	for _, lp := range desc.constLabelPairs {
-		if lp.GetName() == quantileLabel {
-			panic(errQuantileLabelNotAllowed)
-		}
-	}
-
-	if opts.Objectives == nil {
-		opts.Objectives = DefObjectives
-	}
-
-	if opts.MaxAge < 0 {
-		panic(fmt.Errorf("illegal max age MaxAge=%v", opts.MaxAge))
-	}
-	if opts.MaxAge == 0 {
-		opts.MaxAge = DefMaxAge
-	}
-
-	if opts.AgeBuckets == 0 {
-		opts.AgeBuckets = DefAgeBuckets
-	}
-
-	if opts.BufCap == 0 {
-		opts.BufCap = DefBufCap
-	}
-
-	s := &summary{
-		desc: desc,
-
-		objectives:       opts.Objectives,
-		sortedObjectives: make([]float64, 0, len(opts.Objectives)),
-
-		labelPairs: makeLabelPairs(desc, labelValues),
-
-		hotBuf:         make([]float64, 0, opts.BufCap),
-		coldBuf:        make([]float64, 0, opts.BufCap),
-		streamDuration: opts.MaxAge / time.Duration(opts.AgeBuckets),
-	}
-	s.headStreamExpTime = time.Now().Add(s.streamDuration)
-	s.hotBufExpTime = s.headStreamExpTime
-
-	for i := uint32(0); i < opts.AgeBuckets; i++ {
-		s.streams = append(s.streams, s.newStream())
-	}
-	s.headStream = s.streams[0]
-
-	for qu := range s.objectives {
-		s.sortedObjectives = append(s.sortedObjectives, qu)
-	}
-	sort.Float64s(s.sortedObjectives)
-
-	s.init(s) // Init self-collection.
-	return s
-}
-
-type summary struct {
-	selfCollector
-
-	bufMtx sync.Mutex // Protects hotBuf and hotBufExpTime.
-	mtx    sync.Mutex // Protects every other moving part.
-	// Lock bufMtx before mtx if both are needed.
-
-	desc *Desc
-
-	objectives       map[float64]float64
-	sortedObjectives []float64
-
-	labelPairs []*dto.LabelPair
-
-	sum float64
-	cnt uint64
-
-	hotBuf, coldBuf []float64
-
-	streams                          []*quantile.Stream
-	streamDuration                   time.Duration
-	headStream                       *quantile.Stream
-	headStreamIdx                    int
-	headStreamExpTime, hotBufExpTime time.Time
-}
-
-func (s *summary) Desc() *Desc {
-	return s.desc
-}
-
-func (s *summary) Observe(v float64) {
-	s.bufMtx.Lock()
-	defer s.bufMtx.Unlock()
-
-	now := time.Now()
-	if now.After(s.hotBufExpTime) {
-		s.asyncFlush(now)
-	}
-	s.hotBuf = append(s.hotBuf, v)
-	if len(s.hotBuf) == cap(s.hotBuf) {
-		s.asyncFlush(now)
-	}
-}
-
-func (s *summary) Write(out *dto.Metric) error {
-	sum := &dto.Summary{}
-	qs := make([]*dto.Quantile, 0, len(s.objectives))
-
-	s.bufMtx.Lock()
-	s.mtx.Lock()
-	// Swap bufs even if hotBuf is empty to set new hotBufExpTime.
-	s.swapBufs(time.Now())
-	s.bufMtx.Unlock()
-
-	s.flushColdBuf()
-	sum.SampleCount = proto.Uint64(s.cnt)
-	sum.SampleSum = proto.Float64(s.sum)
-
-	for _, rank := range s.sortedObjectives {
-		var q float64
-		if s.headStream.Count() == 0 {
-			q = math.NaN()
-		} else {
-			q = s.headStream.Query(rank)
-		}
-		qs = append(qs, &dto.Quantile{
-			Quantile: proto.Float64(rank),
-			Value:    proto.Float64(q),
-		})
-	}
-
-	s.mtx.Unlock()
-
-	if len(qs) > 0 {
-		sort.Sort(quantSort(qs))
-	}
-	sum.Quantile = qs
-
-	out.Summary = sum
-	out.Label = s.labelPairs
-	return nil
-}
-
-func (s *summary) newStream() *quantile.Stream {
-	return quantile.NewTargeted(s.objectives)
-}
-
-// asyncFlush needs bufMtx locked.
-func (s *summary) asyncFlush(now time.Time) {
-	s.mtx.Lock()
-	s.swapBufs(now)
-
-	// Unblock the original goroutine that was responsible for the mutation
-	// that triggered the compaction.  But hold onto the global non-buffer
-	// state mutex until the operation finishes.
-	go func() {
-		s.flushColdBuf()
-		s.mtx.Unlock()
-	}()
-}
-
-// rotateStreams needs mtx AND bufMtx locked.
-func (s *summary) maybeRotateStreams() {
-	for !s.hotBufExpTime.Equal(s.headStreamExpTime) {
-		s.headStream.Reset()
-		s.headStreamIdx++
-		if s.headStreamIdx >= len(s.streams) {
-			s.headStreamIdx = 0
-		}
-		s.headStream = s.streams[s.headStreamIdx]
-		s.headStreamExpTime = s.headStreamExpTime.Add(s.streamDuration)
-	}
-}
-
-// flushColdBuf needs mtx locked.
-func (s *summary) flushColdBuf() {
-	for _, v := range s.coldBuf {
-		for _, stream := range s.streams {
-			stream.Insert(v)
-		}
-		s.cnt++
-		s.sum += v
-	}
-	s.coldBuf = s.coldBuf[0:0]
-	s.maybeRotateStreams()
-}
-
-// swapBufs needs mtx AND bufMtx locked, coldBuf must be empty.
-func (s *summary) swapBufs(now time.Time) {
-	if len(s.coldBuf) != 0 {
-		panic("coldBuf is not empty")
-	}
-	s.hotBuf, s.coldBuf = s.coldBuf, s.hotBuf
-	// hotBuf is now empty and gets new expiration set.
-	for now.After(s.hotBufExpTime) {
-		s.hotBufExpTime = s.hotBufExpTime.Add(s.streamDuration)
-	}
-}
-
-type quantSort []*dto.Quantile
-
-func (s quantSort) Len() int {
-	return len(s)
-}
-
-func (s quantSort) Swap(i, j int) {
-	s[i], s[j] = s[j], s[i]
-}
-
-func (s quantSort) Less(i, j int) bool {
-	return s[i].GetQuantile() < s[j].GetQuantile()
-}
-
-// SummaryVec is a Collector that bundles a set of Summaries that all share the
-// same Desc, but have different values for their variable labels. This is used
-// if you want to count the same thing partitioned by various dimensions
-// (e.g. HTTP request latencies, partitioned by status code and method). Create
-// instances with NewSummaryVec.
-type SummaryVec struct {
-	*metricVec
-}
-
-// NewSummaryVec creates a new SummaryVec based on the provided SummaryOpts and
-// partitioned by the given label names.
-//
-// Due to the way a Summary is represented in the Prometheus text format and how
-// it is handled by the Prometheus server internally, “quantile” is an illegal
-// label name. NewSummaryVec will panic if this label name is used.
-func NewSummaryVec(opts SummaryOpts, labelNames []string) *SummaryVec {
-	for _, ln := range labelNames {
-		if ln == quantileLabel {
-			panic(errQuantileLabelNotAllowed)
-		}
-	}
-	desc := NewDesc(
-		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
-		opts.Help,
-		labelNames,
-		opts.ConstLabels,
-	)
-	return &SummaryVec{
-		metricVec: newMetricVec(desc, func(lvs ...string) Metric {
-			return newSummary(desc, opts, lvs...)
-		}),
-	}
-}
-
-// GetMetricWithLabelValues returns the Summary for the given slice of label
-// values (same order as the VariableLabels in Desc). If that combination of
-// label values is accessed for the first time, a new Summary is created.
-//
-// It is possible to call this method without using the returned Summary to only
-// create the new Summary but leave it at its starting value, a Summary without
-// any observations.
-//
-// Keeping the Summary for later use is possible (and should be considered if
-// performance is critical), but keep in mind that Reset, DeleteLabelValues and
-// Delete can be used to delete the Summary from the SummaryVec. In that case,
-// the Summary will still exist, but it will not be exported anymore, even if a
-// Summary with the same label values is created later. See also the CounterVec
-// example.
-//
-// An error is returned if the number of label values is not the same as the
-// number of VariableLabels in Desc (minus any curried labels).
-//
-// Note that for more than one label value, this method is prone to mistakes
-// caused by an incorrect order of arguments. Consider GetMetricWith(Labels) as
-// an alternative to avoid that type of mistake. For higher label numbers, the
-// latter has a much more readable (albeit more verbose) syntax, but it comes
-// with a performance overhead (for creating and processing the Labels map).
-// See also the GaugeVec example.
-func (v *SummaryVec) GetMetricWithLabelValues(lvs ...string) (Observer, error) {
-	metric, err := v.metricVec.getMetricWithLabelValues(lvs...)
-	if metric != nil {
-		return metric.(Observer), err
-	}
-	return nil, err
-}
-
-// GetMetricWith returns the Summary for the given Labels map (the label names
-// must match those of the VariableLabels in Desc). If that label map is
-// accessed for the first time, a new Summary is created. Implications of
-// creating a Summary without using it and keeping the Summary for later use are
-// the same as for GetMetricWithLabelValues.
-//
-// An error is returned if the number and names of the Labels are inconsistent
-// with those of the VariableLabels in Desc (minus any curried labels).
-//
-// This method is used for the same purpose as
-// GetMetricWithLabelValues(...string). See there for pros and cons of the two
-// methods.
-func (v *SummaryVec) GetMetricWith(labels Labels) (Observer, error) {
-	metric, err := v.metricVec.getMetricWith(labels)
-	if metric != nil {
-		return metric.(Observer), err
-	}
-	return nil, err
-}
-
-// WithLabelValues works as GetMetricWithLabelValues, but panics where
-// GetMetricWithLabelValues would have returned an error. Not returning an
-// error allows shortcuts like
-//     myVec.WithLabelValues("404", "GET").Observe(42.21)
-func (v *SummaryVec) WithLabelValues(lvs ...string) Observer {
-	s, err := v.GetMetricWithLabelValues(lvs...)
-	if err != nil {
-		panic(err)
-	}
-	return s
-}
-
-// With works as GetMetricWith, but panics where GetMetricWithLabels would have
-// returned an error. Not returning an error allows shortcuts like
-//     myVec.With(prometheus.Labels{"code": "404", "method": "GET"}).Observe(42.21)
-func (v *SummaryVec) With(labels Labels) Observer {
-	s, err := v.GetMetricWith(labels)
-	if err != nil {
-		panic(err)
-	}
-	return s
-}
-
-// CurryWith returns a vector curried with the provided labels, i.e. the
-// returned vector has those labels pre-set for all labeled operations performed
-// on it. The cardinality of the curried vector is reduced accordingly. The
-// order of the remaining labels stays the same (just with the curried labels
-// taken out of the sequence – which is relevant for the
-// (GetMetric)WithLabelValues methods). It is possible to curry a curried
-// vector, but only with labels not yet used for currying before.
-//
-// The metrics contained in the SummaryVec are shared between the curried and
-// uncurried vectors. They are just accessed differently. Curried and uncurried
-// vectors behave identically in terms of collection. Only one must be
-// registered with a given registry (usually the uncurried version). The Reset
-// method deletes all metrics, even if called on a curried vector.
-func (v *SummaryVec) CurryWith(labels Labels) (ObserverVec, error) {
-	vec, err := v.curryWith(labels)
-	if vec != nil {
-		return &SummaryVec{vec}, err
-	}
-	return nil, err
-}
-
-// MustCurryWith works as CurryWith but panics where CurryWith would have
-// returned an error.
-func (v *SummaryVec) MustCurryWith(labels Labels) ObserverVec {
-	vec, err := v.CurryWith(labels)
-	if err != nil {
-		panic(err)
-	}
-	return vec
-}
-
-type constSummary struct {
-	desc       *Desc
-	count      uint64
-	sum        float64
-	quantiles  map[float64]float64
-	labelPairs []*dto.LabelPair
-}
-
-func (s *constSummary) Desc() *Desc {
-	return s.desc
-}
-
-func (s *constSummary) Write(out *dto.Metric) error {
-	sum := &dto.Summary{}
-	qs := make([]*dto.Quantile, 0, len(s.quantiles))
-
-	sum.SampleCount = proto.Uint64(s.count)
-	sum.SampleSum = proto.Float64(s.sum)
-
-	for rank, q := range s.quantiles {
-		qs = append(qs, &dto.Quantile{
-			Quantile: proto.Float64(rank),
-			Value:    proto.Float64(q),
-		})
-	}
-
-	if len(qs) > 0 {
-		sort.Sort(quantSort(qs))
-	}
-	sum.Quantile = qs
-
-	out.Summary = sum
-	out.Label = s.labelPairs
-
-	return nil
-}
-
-// NewConstSummary returns a metric representing a Prometheus summary with fixed
-// values for the count, sum, and quantiles. As those parameters cannot be
-// changed, the returned value does not implement the Summary interface (but
-// only the Metric interface). Users of this package will not have much use for
-// it in regular operations. However, when implementing custom Collectors, it is
-// useful as a throw-away metric that is generated on the fly to send it to
-// Prometheus in the Collect method.
-//
-// quantiles maps ranks to quantile values. For example, a median latency of
-// 0.23s and a 99th percentile latency of 0.56s would be expressed as:
-//     map[float64]float64{0.5: 0.23, 0.99: 0.56}
-//
-// NewConstSummary returns an error if the length of labelValues is not
-// consistent with the variable labels in Desc.
-func NewConstSummary(
-	desc *Desc,
-	count uint64,
-	sum float64,
-	quantiles map[float64]float64,
-	labelValues ...string,
-) (Metric, error) {
-	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
-		return nil, err
-	}
-	return &constSummary{
-		desc:       desc,
-		count:      count,
-		sum:        sum,
-		quantiles:  quantiles,
-		labelPairs: makeLabelPairs(desc, labelValues),
-	}, nil
-}
-
-// MustNewConstSummary is a version of NewConstSummary that panics where
-// NewConstMetric would have returned an error.
-func MustNewConstSummary(
-	desc *Desc,
-	count uint64,
-	sum float64,
-	quantiles map[float64]float64,
-	labelValues ...string,
-) Metric {
-	m, err := NewConstSummary(desc, count, sum, quantiles, labelValues...)
-	if err != nil {
-		panic(err)
-	}
-	return m
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/timer.go b/vendor/github.com/prometheus/client_golang/prometheus/timer.go
deleted file mode 100644
index b8fc5f1..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/timer.go
+++ /dev/null
@@ -1,51 +0,0 @@
-// Copyright 2016 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import "time"
-
-// Timer is a helper type to time functions. Use NewTimer to create new
-// instances.
-type Timer struct {
-	begin    time.Time
-	observer Observer
-}
-
-// NewTimer creates a new Timer. The provided Observer is used to observe a
-// duration in seconds. Timer is usually used to time a function call in the
-// following way:
-//    func TimeMe() {
-//        timer := NewTimer(myHistogram)
-//        defer timer.ObserveDuration()
-//        // Do actual work.
-//    }
-func NewTimer(o Observer) *Timer {
-	return &Timer{
-		begin:    time.Now(),
-		observer: o,
-	}
-}
-
-// ObserveDuration records the duration passed since the Timer was created with
-// NewTimer. It calls the Observe method of the Observer provided during
-// construction with the duration in seconds as an argument. ObserveDuration is
-// usually called with a defer statement.
-//
-// Note that this method is only guaranteed to never observe negative durations
-// if used with Go1.9+.
-func (t *Timer) ObserveDuration() {
-	if t.observer != nil {
-		t.observer.Observe(time.Since(t.begin).Seconds())
-	}
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/untyped.go b/vendor/github.com/prometheus/client_golang/prometheus/untyped.go
deleted file mode 100644
index 0f9ce63..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/untyped.go
+++ /dev/null
@@ -1,42 +0,0 @@
-// Copyright 2014 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-// UntypedOpts is an alias for Opts. See there for doc comments.
-type UntypedOpts Opts
-
-// UntypedFunc works like GaugeFunc but the collected metric is of type
-// "Untyped". UntypedFunc is useful to mirror an external metric of unknown
-// type.
-//
-// To create UntypedFunc instances, use NewUntypedFunc.
-type UntypedFunc interface {
-	Metric
-	Collector
-}
-
-// NewUntypedFunc creates a new UntypedFunc based on the provided
-// UntypedOpts. The value reported is determined by calling the given function
-// from within the Write method. Take into account that metric collection may
-// happen concurrently. If that results in concurrent calls to Write, like in
-// the case where an UntypedFunc is directly registered with Prometheus, the
-// provided function must be concurrency-safe.
-func NewUntypedFunc(opts UntypedOpts, function func() float64) UntypedFunc {
-	return newValueFunc(NewDesc(
-		BuildFQName(opts.Namespace, opts.Subsystem, opts.Name),
-		opts.Help,
-		nil,
-		opts.ConstLabels,
-	), UntypedValue, function)
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/value.go b/vendor/github.com/prometheus/client_golang/prometheus/value.go
deleted file mode 100644
index 9fb7eab..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/value.go
+++ /dev/null
@@ -1,158 +0,0 @@
-// Copyright 2014 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"fmt"
-	"sort"
-
-	dto "github.com/prometheus/client_model/go"
-
-	"github.com/golang/protobuf/proto"
-)
-
-// ValueType is an enumeration of metric types that represent a simple value.
-type ValueType int
-
-// Possible values for the ValueType enum.
-const (
-	_ ValueType = iota
-	CounterValue
-	GaugeValue
-	UntypedValue
-)
-
-// valueFunc is a generic metric for simple values retrieved on collect time
-// from a function. It implements Metric and Collector. Its effective type is
-// determined by ValueType. This is a low-level building block used by the
-// library to back the implementations of CounterFunc, GaugeFunc, and
-// UntypedFunc.
-type valueFunc struct {
-	selfCollector
-
-	desc       *Desc
-	valType    ValueType
-	function   func() float64
-	labelPairs []*dto.LabelPair
-}
-
-// newValueFunc returns a newly allocated valueFunc with the given Desc and
-// ValueType. The value reported is determined by calling the given function
-// from within the Write method. Take into account that metric collection may
-// happen concurrently. If that results in concurrent calls to Write, like in
-// the case where a valueFunc is directly registered with Prometheus, the
-// provided function must be concurrency-safe.
-func newValueFunc(desc *Desc, valueType ValueType, function func() float64) *valueFunc {
-	result := &valueFunc{
-		desc:       desc,
-		valType:    valueType,
-		function:   function,
-		labelPairs: makeLabelPairs(desc, nil),
-	}
-	result.init(result)
-	return result
-}
-
-func (v *valueFunc) Desc() *Desc {
-	return v.desc
-}
-
-func (v *valueFunc) Write(out *dto.Metric) error {
-	return populateMetric(v.valType, v.function(), v.labelPairs, out)
-}
-
-// NewConstMetric returns a metric with one fixed value that cannot be
-// changed. Users of this package will not have much use for it in regular
-// operations. However, when implementing custom Collectors, it is useful as a
-// throw-away metric that is generated on the fly to send it to Prometheus in
-// the Collect method. NewConstMetric returns an error if the length of
-// labelValues is not consistent with the variable labels in Desc.
-func NewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) (Metric, error) {
-	if err := validateLabelValues(labelValues, len(desc.variableLabels)); err != nil {
-		return nil, err
-	}
-	return &constMetric{
-		desc:       desc,
-		valType:    valueType,
-		val:        value,
-		labelPairs: makeLabelPairs(desc, labelValues),
-	}, nil
-}
-
-// MustNewConstMetric is a version of NewConstMetric that panics where
-// NewConstMetric would have returned an error.
-func MustNewConstMetric(desc *Desc, valueType ValueType, value float64, labelValues ...string) Metric {
-	m, err := NewConstMetric(desc, valueType, value, labelValues...)
-	if err != nil {
-		panic(err)
-	}
-	return m
-}
-
-type constMetric struct {
-	desc       *Desc
-	valType    ValueType
-	val        float64
-	labelPairs []*dto.LabelPair
-}
-
-func (m *constMetric) Desc() *Desc {
-	return m.desc
-}
-
-func (m *constMetric) Write(out *dto.Metric) error {
-	return populateMetric(m.valType, m.val, m.labelPairs, out)
-}
-
-func populateMetric(
-	t ValueType,
-	v float64,
-	labelPairs []*dto.LabelPair,
-	m *dto.Metric,
-) error {
-	m.Label = labelPairs
-	switch t {
-	case CounterValue:
-		m.Counter = &dto.Counter{Value: proto.Float64(v)}
-	case GaugeValue:
-		m.Gauge = &dto.Gauge{Value: proto.Float64(v)}
-	case UntypedValue:
-		m.Untyped = &dto.Untyped{Value: proto.Float64(v)}
-	default:
-		return fmt.Errorf("encountered unknown type %v", t)
-	}
-	return nil
-}
-
-func makeLabelPairs(desc *Desc, labelValues []string) []*dto.LabelPair {
-	totalLen := len(desc.variableLabels) + len(desc.constLabelPairs)
-	if totalLen == 0 {
-		// Super fast path.
-		return nil
-	}
-	if len(desc.variableLabels) == 0 {
-		// Moderately fast path.
-		return desc.constLabelPairs
-	}
-	labelPairs := make([]*dto.LabelPair, 0, totalLen)
-	for i, n := range desc.variableLabels {
-		labelPairs = append(labelPairs, &dto.LabelPair{
-			Name:  proto.String(n),
-			Value: proto.String(labelValues[i]),
-		})
-	}
-	labelPairs = append(labelPairs, desc.constLabelPairs...)
-	sort.Sort(LabelPairSorter(labelPairs))
-	return labelPairs
-}
diff --git a/vendor/github.com/prometheus/client_golang/prometheus/vec.go b/vendor/github.com/prometheus/client_golang/prometheus/vec.go
deleted file mode 100644
index 14ed9e8..0000000
--- a/vendor/github.com/prometheus/client_golang/prometheus/vec.go
+++ /dev/null
@@ -1,472 +0,0 @@
-// Copyright 2014 The Prometheus Authors
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-package prometheus
-
-import (
-	"fmt"
-	"sync"
-
-	"github.com/prometheus/common/model"
-)
-
-// metricVec is a Collector to bundle metrics of the same name that differ in
-// their label values. metricVec is not used directly (and therefore
-// unexported). It is used as a building block for implementations of vectors of
-// a given metric type, like GaugeVec, CounterVec, SummaryVec, and HistogramVec.
-// It also handles label currying. It uses basicMetricVec internally.
-type metricVec struct {
-	*metricMap
-
-	curry []curriedLabelValue
-
-	// hashAdd and hashAddByte can be replaced for testing collision handling.
-	hashAdd     func(h uint64, s string) uint64
-	hashAddByte func(h uint64, b byte) uint64
-}
-
-// newMetricVec returns an initialized metricVec.
-func newMetricVec(desc *Desc, newMetric func(lvs ...string) Metric) *metricVec {
-	return &metricVec{
-		metricMap: &metricMap{
-			metrics:   map[uint64][]metricWithLabelValues{},
-			desc:      desc,
-			newMetric: newMetric,
-		},
-		hashAdd:     hashAdd,
-		hashAddByte: hashAddByte,
-	}
-}
-
-// DeleteLabelValues removes the metric where the variable labels are the same
-// as those passed in as labels (same order as the VariableLabels in Desc). It
-// returns true if a metric was deleted.
-//
-// It is not an error if the number of label values is not the same as the
-// number of VariableLabels in Desc. However, such inconsistent label count can
-// never match an actual metric, so the method will always return false in that
-// case.
-//
-// Note that for more than one label value, this method is prone to mistakes
-// caused by an incorrect order of arguments. Consider Delete(Labels) as an
-// alternative to avoid that type of mistake. For higher label numbers, the
-// latter has a much more readable (albeit more verbose) syntax, but it comes
-// with a performance overhead (for creating and processing the Labels map).
-// See also the CounterVec example.
-func (m *metricVec) DeleteLabelValues(lvs ...string) bool {
-	h, err := m.hashLabelValues(lvs)
-	if err != nil {
-		return false
-	}
-
-	return m.metricMap.deleteByHashWithLabelValues(h, lvs, m.curry)
-}
-
-// Delete deletes the metric where the variable labels are the same as those
-// passed in as labels. It returns true if a metric was deleted.
-//
-// It is not an error if the number and names of the Labels are inconsistent
-// with those of the VariableLabels in Desc. However, such inconsistent Labels
-// can never match an actual metric, so the method will always return false in
-// that case.
-//
-// This method is used for the same purpose as DeleteLabelValues(...string). See
-// there for pros and cons of the two methods.
-func (m *metricVec) Delete(labels Labels) bool {
-	h, err := m.hashLabels(labels)
-	if err != nil {
-		return false
-	}
-
-	return m.metricMap.deleteByHashWithLabels(h, labels, m.curry)
-}
-
-func (m *metricVec) curryWith(labels Labels) (*metricVec, error) {
-	var (
-		newCurry []curriedLabelValue
-		oldCurry = m.curry
-		iCurry   int
-	)
-	for i, label := range m.desc.variableLabels {
-		val, ok := labels[label]
-		if iCurry < len(oldCurry) && oldCurry[iCurry].index == i {
-			if ok {
-				return nil, fmt.Errorf("label name %q is already curried", label)
-			}
-			newCurry = append(newCurry, oldCurry[iCurry])
-			iCurry++
-		} else {
-			if !ok {
-				continue // Label stays uncurried.
-			}
-			newCurry = append(newCurry, curriedLabelValue{i, val})
-		}
-	}
-	if l := len(oldCurry) + len(labels) - len(newCurry); l > 0 {
-		return nil, fmt.Errorf("%d unknown label(s) found during currying", l)
-	}
-
-	return &metricVec{
-		metricMap:   m.metricMap,
-		curry:       newCurry,
-		hashAdd:     m.hashAdd,
-		hashAddByte: m.hashAddByte,
-	}, nil
-}
-
-func (m *metricVec) getMetricWithLabelValues(lvs ...string) (Metric, error) {
-	h, err := m.hashLabelValues(lvs)
-	if err != nil {
-		return nil, err
-	}
-
-	return m.metricMap.getOrCreateMetricWithLabelValues(h, lvs, m.curry), nil
-}
-
-func (m *metricVec) getMetricWith(labels Labels) (Metric, error) {
-	h, err := m.hashLabels(labels)
-	if err != nil {
-		return nil, err
-	}
-
-	return m.metricMap.getOrCreateMetricWithLabels(h, labels, m.curry), nil
-}
-
-func (m *metricVec) hashLabelValues(vals []string) (uint64, error) {
-	if err := validateLabelValues(vals, len(m.desc.variableLabels)-len(m.curry)); err != nil {
-		return 0, err
-	}
-
-	var (
-		h             = hashNew()
-		curry         = m.curry
-		iVals, iCurry int
-	)
-	for i := 0; i < len(m.desc.variableLabels); i++ {
-		if iCurry < len(curry) && curry[iCurry].index == i {
-			h = m.hashAdd(h, curry[iCurry].value)
-			iCurry++
-		} else {
-			h = m.hashAdd(h, vals[iVals])
-			iVals++
-		}
-		h = m.hashAddByte(h, model.SeparatorByte)
-	}
-	return h, nil
-}
-
-func (m *metricVec) hashLabels(labels Labels) (uint64, error) {
-	if err := validateValuesInLabels(labels, len(m.desc.variableLabels)-len(m.curry)); err != nil {
-		return 0, err
-	}
-
-	var (
-		h      = hashNew()
-		curry  = m.curry
-		iCurry int
-	)
-	for i, label := range m.desc.variableLabels {
-		val, ok := labels[label]
-		if iCurry < len(curry) && curry[iCurry].index == i {
-			if ok {
-				return 0, fmt.Errorf("label name %q is already curried", label)
-			}
-			h = m.hashAdd(h, curry[iCurry].value)
-			iCurry++
-		} else {
-			if !ok {
-				return 0, fmt.Errorf("label name %q missing in label map", label)
-			}
-			h = m.hashAdd(h, val)
-		}
-		h = m.hashAddByte(h, model.SeparatorByte)
-	}
-	return h, nil
-}
-
-// metricWithLabelValues provides the metric and its label values for
-// disambiguation on hash collision.
-type metricWithLabelValues struct {
-	values []string
-	metric Metric
-}
-
-// curriedLabelValue sets the curried value for a label at the given index.
-type curriedLabelValue struct {
-	index int
-	value string
-}
-
-// metricMap is a helper for metricVec and shared between differently curried
-// metricVecs.
-type metricMap struct {
-	mtx       sync.RWMutex // Protects metrics.
-	metrics   map[uint64][]metricWithLabelValues
-	desc      *Desc
-	newMetric func(labelValues ...string) Metric
-}
-
-// Describe implements Collector. It will send exactly one Desc to the provided
-// channel.
-func (m *metricMap) Describe(ch chan<- *Desc) {
-	ch <- m.desc
-}
-
-// Collect implements Collector.
-func (m *metricMap) Collect(ch chan<- Metric) {
-	m.mtx.RLock()
-	defer m.mtx.RUnlock()
-
-	for _, metrics := range m.metrics {
-		for _, metric := range metrics {
-			ch <- metric.metric
-		}
-	}
-}
-
-// Reset deletes all metrics in this vector.
-func (m *metricMap) Reset() {
-	m.mtx.Lock()
-	defer m.mtx.Unlock()
-
-	for h := range m.metrics {
-		delete(m.metrics, h)
-	}
-}
-
-// deleteByHashWithLabelValues removes the metric from the hash bucket h. If
-// there are multiple matches in the bucket, use lvs to select a metric and
-// remove only that metric.
-func (m *metricMap) deleteByHashWithLabelValues(
-	h uint64, lvs []string, curry []curriedLabelValue,
-) bool {
-	m.mtx.Lock()
-	defer m.mtx.Unlock()
-
-	metrics, ok := m.metrics[h]
-	if !ok {
-		return false
-	}
-
-	i := findMetricWithLabelValues(metrics, lvs, curry)
-	if i >= len(metrics) {
-		return false
-	}
-
-	if len(metrics) > 1 {
-		m.metrics[h] = append(metrics[:i], metrics[i+1:]...)
-	} else {
-		delete(m.metrics, h)
-	}
-	return true
-}
-
-// deleteByHashWithLabels removes the metric from the hash bucket h. If there
-// are multiple matches in the bucket, use lvs to select a metric and remove
-// only that metric.
-func (m *metricMap) deleteByHashWithLabels(
-	h uint64, labels Labels, curry []curriedLabelValue,
-) bool {
-	m.mtx.Lock()
-	defer m.mtx.Unlock()
-
-	metrics, ok := m.metrics[h]
-	if !ok {
-		return false
-	}
-	i := findMetricWithLabels(m.desc, metrics, labels, curry)
-	if i >= len(metrics) {
-		return false
-	}
-
-	if len(metrics) > 1 {
-		m.metrics[h] = append(metrics[:i], metrics[i+1:]...)
-	} else {
-		delete(m.metrics, h)
-	}
-	return true
-}
-
-// getOrCreateMetricWithLabelValues retrieves the metric by hash and label value
-// or creates it and returns the new one.
-//
-// This function holds the mutex.
-func (m *metricMap) getOrCreateMetricWithLabelValues(
-	hash uint64, lvs []string, curry []curriedLabelValue,
-) Metric {
-	m.mtx.RLock()
-	metric, ok := m.getMetricWithHashAndLabelValues(hash, lvs, curry)
-	m.mtx.RUnlock()
-	if ok {
-		return metric
-	}
-
-	m.mtx.Lock()
-	defer m.mtx.Unlock()
-	metric, ok = m.getMetricWithHashAndLabelValues(hash, lvs, curry)
-	if !ok {
-		inlinedLVs := inlineLabelValues(lvs, curry)
-		metric = m.newMetric(inlinedLVs...)
-		m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: inlinedLVs, metric: metric})
-	}
-	return metric
-}
-
-// getOrCreateMetricWithLabelValues retrieves the metric by hash and label value
-// or creates it and returns the new one.
-//
-// This function holds the mutex.
-func (m *metricMap) getOrCreateMetricWithLabels(
-	hash uint64, labels Labels, curry []curriedLabelValue,
-) Metric {
-	m.mtx.RLock()
-	metric, ok := m.getMetricWithHashAndLabels(hash, labels, curry)
-	m.mtx.RUnlock()
-	if ok {
-		return metric
-	}
-
-	m.mtx.Lock()
-	defer m.mtx.Unlock()
-	metric, ok = m.getMetricWithHashAndLabels(hash, labels, curry)
-	if !ok {
-		lvs := extractLabelValues(m.desc, labels, curry)
-		metric = m.newMetric(lvs...)
-		m.metrics[hash] = append(m.metrics[hash], metricWithLabelValues{values: lvs, metric: metric})
-	}
-	return metric
-}
-
-// getMetricWithHashAndLabelValues gets a metric while handling possible
-// collisions in the hash space. Must be called while holding the read mutex.
-func (m *metricMap) getMetricWithHashAndLabelValues(
-	h uint64, lvs []string, curry []curriedLabelValue,
-) (Metric, bool) {
-	metrics, ok := m.metrics[h]
-	if ok {
-		if i := findMetricWithLabelValues(metrics, lvs, curry); i < len(metrics) {
-			return metrics[i].metric, true
-		}
-	}
-	return nil, false
-}
-
-// getMetricWithHashAndLabels gets a metric while handling possible collisions in
-// the hash space. Must be called while holding read mutex.
-func (m *metricMap) getMetricWithHashAndLabels(
-	h uint64, labels Labels, curry []curriedLabelValue,
-) (Metric, bool) {
-	metrics, ok := m.metrics[h]
-	if ok {
-		if i := findMetricWithLabels(m.desc, metrics, labels, curry); i < len(metrics) {
-			return metrics[i].metric, true
-		}
-	}
-	return nil, false
-}
-
-// findMetricWithLabelValues returns the index of the matching metric or
-// len(metrics) if not found.
-func findMetricWithLabelValues(
-	metrics []metricWithLabelValues, lvs []string, curry []curriedLabelValue,
-) int {
-	for i, metric := range metrics {
-		if matchLabelValues(metric.values, lvs, curry) {
-			return i
-		}
-	}
-	return len(metrics)
-}
-
-// findMetricWithLabels returns the index of the matching metric or len(metrics)
-// if not found.
-func findMetricWithLabels(
-	desc *Desc, metrics []metricWithLabelValues, labels Labels, curry []curriedLabelValue,
-) int {
-	for i, metric := range metrics {
-		if matchLabels(desc, metric.values, labels, curry) {
-			return i
-		}
-	}
-	return len(metrics)
-}
-
-func matchLabelValues(values []string, lvs []string, curry []curriedLabelValue) bool {
-	if len(values) != len(lvs)+len(curry) {
-		return false
-	}
-	var iLVs, iCurry int
-	for i, v := range values {
-		if iCurry < len(curry) && curry[iCurry].index == i {
-			if v != curry[iCurry].value {
-				return false
-			}
-			iCurry++
-			continue
-		}
-		if v != lvs[iLVs] {
-			return false
-		}
-		iLVs++
-	}
-	return true
-}
-
-func matchLabels(desc *Desc, values []string, labels Labels, curry []curriedLabelValue) bool {
-	if len(values) != len(labels)+len(curry) {
-		return false
-	}
-	iCurry := 0
-	for i, k := range desc.variableLabels {
-		if iCurry < len(curry) && curry[iCurry].index == i {
-			if values[i] != curry[iCurry].value {
-				return false
-			}
-			iCurry++
-			continue
-		}
-		if values[i] != labels[k] {
-			return false
-		}
-	}
-	return true
-}
-
-func extractLabelValues(desc *Desc, labels Labels, curry []curriedLabelValue) []string {
-	labelValues := make([]string, len(labels)+len(curry))
-	iCurry := 0
-	for i, k := range desc.variableLabels {
-		if iCurry < len(curry) && curry[iCurry].index == i {
-			labelValues[i] = curry[iCurry].value
-			iCurry++
-			continue
-		}
-		labelValues[i] = labels[k]
-	}
-	return labelValues
-}
-
-func inlineLabelValues(lvs []string, curry []curriedLabelValue) []string {
-	labelValues := make([]string, len(lvs)+len(curry))
-	var iCurry, iLVs int
-	for i := range labelValues {
-		if iCurry < len(curry) && curry[iCurry].index == i {
-			labelValues[i] = curry[iCurry].value
-			iCurry++
-			continue
-		}
-		labelValues[i] = lvs[iLVs]
-		iLVs++
-	}
-	return labelValues
-}