curl and libcurl 7.71.0

 Public curl releases:         192
 Command line options:         232
 curl_easy_setopt() options:   270
 Public functions in libcurl:  82
 Contributors:                 2175

This release includes the following changes:

 o CURLOPT_SSL_OPTIONS: optional use of Windows' CA store (with openssl) [10]
 o tool: Add option --retry-all-errors to retry on any error [27]

This release includes the following bugfixes:

 o *_sspi: fix bad uses of CURLE_NOT_BUILT_IN [21]
 o appveyor: disable flaky test 1501 and ignore broken 1056
 o appveyor: disable test 1139 instead of ignoring it
 o asyn-*: remove support for never-used NULL entry pointers [19]
 o cirrus: disable SFTP and SCP tests [7]
 o CMake: add ENABLE_ALT_SVC option
 o CMake: add HTTP/3 support (ngtcp2+nghttp3, quiche) [34]
 o CMake: do not build test programs by default [30]
 o CMake: fix runtests.pl with CMake, add new test targets [29]
 o connect: make happy eyeballs work for QUIC (again) [16]
 o doc: add missing closing parenthesis in CURLINFO_SSL_VERIFYRESULT.3 [5]
 o doc: Rename VERSIONS to VERSIONS.md as it already has Markdown syntax [20]
 o docs/HTTP3: add qlog to the quiche build instruction
 o dynbuf: introduce internal generic dynamic buffer functions [17]
 o easy: fix dangling pointer on easy_perform fail [26]
 o examples: remove asiohiper.cpp [4]
 o GnuTLS: Backend support for CURLINFO_SSL_VERIFYRESULT [9]
 o http2: simplify and clean up trailer handling [6]
 o libcurl.pc: Merge Libs.private into Libs for static-only builds [28]
 o libssh2: set the expected total size in SCP upload init [2]
 o libtest/cmake: Remove commented code [13]
 o list-only.d: this option existed already in 4.0
 o ngtcp2: introduce qlog support [23]
 o quiche: enable qlog output [14]
 o runtests: remove sleep calls [18]
 o runtests: show elapsed test time with higher precision (ms)
 o select: fix overflow protection in Curl_socket_check [22]
 o sockfilt: make select_ws stop waiting on exit signal event
 o test1177: look for curl.h in source directory [1]
 o test1238: avoid tftpd being busy for tests shortly following [33]
 o test613.pl: make tests 613 and 614 work with OpenSSH for Windows [8]
 o test75: Remove precheck test
 o tests: add support for SSH server variant specific transfer paths [24]
 o tests: make test 1248 + 1249 use %NOLISTENPORT [3]
 o tests: pick a random port number for SSH [12]
 o tests: run stunnel for HTTPS and FTPS on dynamic ports [11]
 o travis: add "qlog" as feature in the quiche build
 o travis: Add ngtcp2 and quiche tests for CMake
 o url: reject too long input when parsing credentials [25]
 o url: sort the protocol schemes in rough popularity order [32]
 o urlapi: accept :: as a valid IPv6 address [15]
 o write-out.d: added "response_code"

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:

  Dan Fandrich, Daniel Stenberg, Emil Engler, Gilles Vollant, James Le Cuirot,
  Kamil Dudka, Kane York, Lucas Pardue, Marcel Raad, Marc Hörsken,
  Michael Kaufmann, Murugan Balraj, Pavel Volgarev, Peter Wang, Peter Wu,
  Ray Satiro, Rikard Falkeborn, rl1987 on github, Samuel Marks,
  Thomas Bouzerar,
  (20 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=5310
 [2] = https://curl.haxx.se/mail/archive-2020-05/0000.html
 [3] = https://curl.haxx.se/bug/?i=5318
 [4] = https://curl.haxx.se/bug/?i=5090
 [5] = https://curl.haxx.se/bug/?i=5320
 [6] = https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=22030
 [7] = https://curl.haxx.se/bug/?i=5315
 [8] = https://curl.haxx.se/bug/?i=5328
 [9] = https://curl.haxx.se/bug/?i=5287
 [10] = https://curl.haxx.se/bug/?i=4346
 [11] = https://curl.haxx.se/bug/?i=5267
 [12] = https://curl.haxx.se/bug/?i=5273
 [13] = https://curl.haxx.se/bug/?i=5311
 [14] = https://curl.haxx.se/bug/?i=5341
 [15] = https://curl.haxx.se/bug/?i=5344
 [16] = https://curl.haxx.se/bug/?i=5334
 [17] = https://curl.haxx.se/bug/?i=5300
 [18] = https://curl.haxx.se/bug/?i=5323
 [19] = https://curl.haxx.se/bug/?i=5324
 [20] = https://curl.haxx.se/bug/?i=5325
 [21] = https://curl.haxx.se/bug/?i=5355
 [22] = https://curl.haxx.se/bug/?i=5286
 [23] = https://curl.haxx.se/bug/?i=5353
 [24] = https://curl.haxx.se/bug/?i=5298
 [25] = https://curl.haxx.se/bug/?i=5383
 [26] = https://curl.haxx.se/bug/?i=5363
 [27] = https://curl.haxx.se/bug/?i=5185
 [28] = https://curl.haxx.se/bug/?i=5373
 [29] = https://curl.haxx.se/bug/?i=5358
 [30] = https://curl.haxx.se/bug/?i=5368
 [32] = https://curl.haxx.se/bug/?i=5377
 [33] = https://curl.haxx.se/bug/?i=5364
 [34] = https://curl.haxx.se/bug/?i=5359