[ticket/9871] Update version check file to use json format

PHPBB3-9871
[ticket/9871] Use $request->variable instead of request_var

PHPBB3-9871
[ticket/9871] Restore get_remote_file

PHPBB3-9871
[ticket/9871] Restore phpbb_version_compare

PHPBB3-9871
[ticket/9871] Mark test as slow

PHPBB3-9871
[ticket/9871] Typehint and comment on var types

PHPBB3-9871
[ticket/9871] Fix tests

PHPBB3-9871
[ticket/12202] Apply htmlspecialchars to style.cfg data

PHPBB3-12202
[ticket/12202] Use copyright symbol in style.cfg files

PHPBB3-12202
[ticket/12202] Test for parse_cfg_file

PHPBB3-12202
[ticket/12202] Fix tests

PHPBB3-12202
[ticket/12202] Can't call htmlspecialchars before checking for quotes

PHPBB3-12202
[ticket/9871] Restore get_remote_file_test

PHPBB3-9871
[ticket/9871] Allow setting the host/file to load for the version class

PHPBB3-9871
[ticket/11581] Add test to check UCP_PM is enabled/disabled correctly

PHPBB3-11581
[ticket/11581] Enabled private messages after tests

PHPBB3-11581
[ticket/11581] Fix year in copyright header

PHPBB3-11581
[ticket/12262] Also find vars array when it's defined in the trigger_event()

PHPBB3-12262
[ticket/12262] Fix location list for acp events with "Locations:"

PHPBB3-12262
[ticket/9871] Option to force the stability when checking for updates

PHPBB3-9871