weechat: Update to 2.8

== Version 2.8 (2020-03-29)

New features::

  * core: add variable "old_full_name" in buffer, set during buffer renaming (issue #1428)
  * core: add debug option "-d" in command /eval (issue #1434)
  * api: add functions crypto_hash and crypto_hash_pbkdf2
  * api: add info "auto_connect" (issue #1453)
  * api: add info "weechat_headless" (issue #1433)
  * buflist: add pointer "window" in bar item evaluation
  * irc: add support of fake servers (no I/O, for testing purposes)
  * relay: accept hash of password in init command of weechat protocol with option "password_hash" (PBKDF2, SHA256, SHA512)
  * relay: reject client with weechat protocol if password or totp is received in init command but not set in WeeChat (issue #1435)

Bug fixes::

  * core: fix memory leak in completion
  * core: flush stdout/stderr before forking in hook_process function (issue #1441)
  * core: fix evaluation of condition with nested "if" (issue #1434)
  * irc: split AUTHENTICATE message in 400-byte chunks (issue #1459)
  * irc: copy temporary server flag in command /server copy
  * irc: add nick changes in the hotlist (except self nick change)
  * irc: case-insensitive comparison on incoming CTCP command, force upper case on CTCP replies (issue #1439)
  * irc: fix memory leak when the channel topic is changed
  * logger: fix crash when logging is disabled on a buffer and the log file was deleted in the meanwhile, when option logger.file.info_lines is on (issue #1444)
  * php: fix crash when loading script with PHP 7.4 (issue #1452)
  * relay: update buffers synchronization when buffers are renamed (issue #1428)
  * script: fix memory leak in read of script repository file if it has invalid content
  * script: fix unexpected display of scripts list in buffer with command /script list -i
  * xfer: send signal "xfer_ended" after the received file has been renamed (issue #1438)

Tests::

  * scripts: fix generation of test scripts with Python 3.8
  * unit: add tests on IRC protocol functions and callbacks
  * unit: add tests on function secure_derive_key
  * unit: add tests on functions util_get_time_diff and util_file_get_content

Build::

  * core: fix Cygwin build
  * guile: add detection of Guile 3.0.0 (issue #1442)
  * irc: fix build with GnuTLS < 3.1.0 (issue #1431)
  * php: add detection of PHP 7.4
  * ruby: add detection of Ruby 2.7 (issue #1455)

(nia)