Added 'assigned_to' attribute to School as a forreign key to User.
The plan is to assign a school to a single user (TODO: chosen at sign-up).
 - Therefore, a user_name will be associated with a school
 - If you find your school is taken, contact admin.
[CHANGES] Lots of things.
Schools are now associated with user names. (One school for a user)
+ Students (registration page) now redirects if no school is associated with profile.
+ A message is shown in a selected school is already associated with another user.
+ Student registration now has SchoolName in title.
Forgot forms.py in last commit. My bad.
[FIX] assigned_to can now be None. New user can now select school with which to be associated (which will update the database entry with their user name).
Merge remote-tracking branch 'frankr/201312U' into monday

Conflicts:
	uctMaths/competition/views.py