[ticket/11760] Use phpbb_version_compare() wrapper

PHPBB3-11760
[ticket/11801] removed some whitespace and added missing semi colon's in css

PHPBB3-11801
Merge remote-tracking branch 'Elsensee/ticket/11760' into develop

# By Oliver Schramm
# Via Oliver Schramm
* Elsensee/ticket/11760:
  [ticket/11760] Use phpbb_version_compare() wrapper
Merge remote-tracking branch 'Prosk8er/ticket/11801' into develop-olympus

* Prosk8er/ticket/11801:
  [ticket/11801] removed some whitespace and added missing semi colon's in css
Merge branch 'develop-olympus' into develop

* develop-olympus:
  [ticket/11801] removed some whitespace and added missing semi colon's in css

Conflicts:
	phpBB/styles/prosilver/theme/colours.css