[ticket/7707] Add get_username_string() where possible

PHPBB3-7707
[ticket/7707] Remove unnecessary variables

PHPBB3-7707
[ticket/7707] Add get_username_string() once more

PHPBB3-7707
[ticket/7707] Remove unnecessary variables

PHPBB3-7707
[ticket/12150] Add options to acp

PHPBB3-12150
[ticket/12150] Add prune columns to schema files and migration file

PHPBB3-12150
[ticket/12150] Add file and caller for pruning shadow topics

PHPBB3-12150
[ticket/12150] Add missing prune settings variables in acp_forums

PHPBB3-12150
[ticket/12150] Add missing space to query for shadow topics

PHPBB3-12150
[ticket/12150] Add functional tests for pruning shadow topics

PHPBB3-12150
[ticket/12150] Use shorter column names for prune settings

All columns were renamed from having prune_shadow_topics as namebase to just
prune_shadow.
A missing column was also added to the migration file's remove_schema() method.

PHPBB3-12150
[ticket/12150] Use log service instead of add_log() function

PHPBB3-12150
Merge branch 'develop-ascraeus' of https://github.com/phpbb/phpbb into ticket/12150
[ticket/12150] Update schema files for prune shadow topics

PHPBB3-12150
[ticket/11962] Resize posted images to fit and give them a class

PHPBB3-11962
[ticket/12333] Add Template Event overall_header_body_after

PHPBB3-12333
[ticket/12333] Change event name

PHPBB3-12333
[ticket/12339] Add Event core.page_header_after

PHPBB3-12339
[ticket/7707] Add comma to last entry of arrays

PHPBB3-7707
[ticket/12342] Use prop() instead of attr() for boolean properties

PHPBB3-12342