BAC-821 add isBlockedCheck in SpecialAchievementsCustomize, and add PreventBlockedUsers trait (used by WikiaController) which can prevent a user from accessing/editing content if they're blocked.

this functionality is opt-in, and currently only used by WikiFeaturesSpecialController (Special:WikiFeatures)
formatting some code to wikia standards
updating static vars to make more sense
extending PreventBlockedUsers trait with PreventBlockedUsersThrowsError so classes that use these don't need to specify the action, removing vars from PreventBlockedUsers, and removing "use PreventBlockedUsers;" from base WikiaController
Merge remote-tracking branch 'origin/dev' into BAC-821
fixed/added some documentation
Merge pull request #1586 from Wikia/BAC-821

BAC-821 - prevent blocked users from taking action
Video (vid-911): VideoPageTool - update publish date
Merge pull request #1699 from Wikia/vid-911

Video (vid-911): VideoPageTool - update publish date
VID-790 adding breadcrumbs to the top of the video page admin form
removing unused code
Localisation updates from http://translatewiki.net.
VID-917 fixing scroll bar on video home page
removing unnecessary semicolons
Merge pull request #1700 from Wikia/VID-790-breadcrumbs

VID-790 adding breadcrumbs to the top of the video page admin form
Merge pull request #1702 from Wikia/VID-917-scroll

VID-917 fixing scroll bar on video home page
Merge branch 'dev' into VideoSprint34
send forever: true to backend on confirmed keep
Merge pull request #1716 from Wikia/vid-855-add-work

send forever: true to backend on confirmed keep
Merge branch 'VideoSprint34' into vid-758