[ticket/11824] Add option for mod_rewrite

PHPBB3-11824
[ticket/11824] Fix logic

PHPBB3-11824
[ticket/11824] Fix smilies

PHPBB3-11824
[ticket/11824] Remove unused globals

PHPBB3-11824
[ticket/11824] Change copyright year in migration file

PHPBB3-11824
[ticket/11824] Correct a comment

PHPBB3-11824
[ticket/11824] Add tests for urls with mod_rewrite enabled

PHPBB3-11824
[ticket/11824] Revert changes to functions_content.php

These will be fixed in another PR

PHPBB3-11824
[ticket/11824] Update language string for board settings

PHPBB3-11824
[ticket/11824] Reorganize test file

PHPBB3-11824
[ticket/11824] Revert changes in functions.php

These will be added in another PR

PHPBB3-11824
[ticket/11824] Fix comment wording

PHPBB3-11824
Merge remote-tracking branch 'imkingdavid/ticket/11824' into develop