[ticket/11062] Load new strings from user's language file if provided

PHPBB3-11062
[ticket/11062] If user's language is english there is no further work needed

PHPBB3-11062
Merge remote-tracking branch 'remotes/Elsensee/ticket/11062' into develop-olympus

# By Oliver Schramm
# Via Oliver Schramm
* remotes/Elsensee/ticket/11062:
  [ticket/11062] If user's language is english there is no further work needed
  [ticket/11062] Load new strings from user's language file if provided