irc: add "server-time" in help of server option "capabilities"
core: fix modifier "weechat_print": discard only one line when several lines are displayed in same message (closes #171)

When several lines are displayed in a message (separated by "\n"), the
modifier "weechat_print" will now discard just one line (if return value is
an empty string), instead of discarding the whole message.
core: fix typo in French translation of /help set
core: update German translations
doc: update German auto-generated files
core: add contributor in AUTHORS.asciidoc
trigger: fix regex used in default triggers to hide passwords (closes #172)

"\S" is not supported on *BSD, so it is replaced by "[^ ]" (which should be
enough, since there should be no tabs or other whitespace different from
spaces in command line).
script: fix crash on "/script update" if a script detail is displayed in buffer (closes #177)
trigger: add option "restore" in command /trigger
core: add command to restore default triggers that have changed in version 1.1 (release notes)
core: update German translations
doc: update German documentation
doc: update German documentation
doc: update German auto-generated files
core: allow incomplete commands if unambiguous (task #5419)
doc: update auto-generated files with WeeChat options
core: add new option weechat.look.command_incomplete in ChangeLog
core: fix typo: unambigous -> unambiguous
core: fix typo: too much calls -> too many calls
core: fix error message in case of ambiguous incomplete command