fixing match tag validation
Merge branch 'master' of github.com:andrewhl/AdvancedStudyRoom

* 'master' of github.com:andrewhl/AdvancedStudyRoom:
  create rollover registrations without updated_at and created_at dates
  fix unassigned registrations duplication during rollover
  allow admin to quit unassigned players
  update rollover to use august as new event base add completed at to the match details page
  fix match redirection after validation and tag
  hide join button in events result for closed events