Add User Faculty label fix.

"admin only" doesn't make sense when instructors can also select
faculties.
Fix master question losing responses & deletion.

Fix master question losing responses:
Ticket #451: http://ipeer.ctlt.ubc.ca/trac/ticket/451

When a master question is loaded, the response array it returns includes
the ID number of the responses. Since responses can only belong to 1
question, this results in the new question co-opting ownership of these
responses.

Fix master question deletion:
All questions actually weren't being deleted for some reason. But only
the master questions show up as a symptom since they're the only ones
still accessible by the user after deletion. habtmDelete didn't properly
delete everything, added a manual delete as a quick fix.