Curl and libcurl 7.51.0

 Public curl releases:         160
 Command line options:         185
 curl_easy_setopt() options:   224
 Public functions in libcurl:  61
 Contributors:                 1445

This release includes the following changes:

 o nss: additional cipher suites are now accepted by CURLOPT_SSL_CIPHER_LIST

This release includes the following bugfixes:

 o openssl: fix per-thread memory leak usiong 1.0.1 or 1.0.2 [1]
 o http: accept "Transfer-Encoding: chunked" for HTTP/2 as well [2]
 o LICENSE-MIXING.md: update with mbedTLS dual licensing [3]
 o examples/imap-append: Set size of data to be uploaded [4]
 o test2048: fix url
 o darwinssl: disable RC4 cipher-suite support
 o CURLOPT_PINNEDPUBLICKEY.3: fix the AVAILABILITY formatting
 o openssl: don’t call CRYTPO_cleanup_all_ex_data [5]
 o libressl: fix version output [6]

This release includes the following known bugs:

 o see docs/KNOWN_BUGS (https://curl.haxx.se/docs/knownbugs.html)

This release would not have looked like this without help, code, reports and
advice from friends like these:

  Akshay Vernekar, Bernard Spil, Daniel Gustafsson, Daniel Stenberg,
  lukaszgn on github, Nick Zitzmann, Ray Satiro, Todd Short, Tony Kelman,
  (9 contributors)

        Thanks! (and sorry if I forgot to mention someone)

References to bug reports and discussions on issues:

 [1] = https://curl.haxx.se/bug/?i=964
 [2] = https://curl.haxx.se/bug/?i=1013
 [3] = https://curl.haxx.se/bug/?i=1019
 [4] = https://curl.haxx.se/bug/?i=1011
 [5] = https://curl.haxx.se/mail/lib-2016-09/0045.html
 [6] = https://curl.haxx.se/bug/?i=1029