[ticket/12991] Have events after/before "add warning" field - user and post

PHPBB3-12991
[ticket/12661] Load extensions templates from "all" folder by render()

PHPBB3-12661
[ticket/12661] Add template test

PHPBB3-12661
[ticket/12661] Add new line at the end  of files

PHPBB3-12661
[ticket/12991] Correct language mistakes

PHPBB3-12991
Merge pull request #2887 from Pico/ticket/12991

[ticket/12991] Have events after/before "add warning" field - user and post
Merge pull request #2908 from Pico/t/12661

[ticket/12661] Load extensions templates from "all" folder by render()
Merge pull request #2 from phpbb/develop-ascraeus

Update from origin