Bug/quiz 62

I believe the mass of students he's seeing has to do with shopping period. They get added to enrollees for a short amount of time and after shopping period, they remain because they've been added to the local list.

My solution is to do a "cleanup" when going through the users setup. Before new users are added, it will check all existing users against the list of users it gets from icommons, and it will remove anyone who is labelled as an enrollee, but isn't in the new list of course personell. 

@arthurian please review