refactors to use has_many throug association
removes helper tests
removes old should syntax from user_pages_spec.rb
fixes invitation model to use :through association
fixes the problem with some resources being singular in the routes files
fixes the factories and refators tests
adds remove action to invitations
various changes I have forget to commit to ired to seperate...
adds Invitator to events controler
Merge branch 'remodeling_user_invitation_event_relationship'