Easier adding of users in bulk; message to tell of successful creation; allow teachers to belong to a group.
made small cleanup re: code review; found bug in still differentiating teacher/student, made code more flexible to compensate.  In future, use similar techniques to make cross-app browsing more fluid.
fixed up nits, used script to identify mess.  Will make code review challenging...
Merge branch 'add_user_ux' of github.com:bcipolli/ka-lite into add_user_ux

Conflicts:
	kalite/securesync/views.py
Merge pull request #154 from bcipolli/add_user_ux

Better user registration UX on the distributed server