Delete projects admin interface

[michaelwood]

Add a delete projects page

• A list of projects with checkboxes to select ones to delete
• A password held in the django settings.py
• A confirm delete prompt
• Documentation on the admin docs
• If password not set/blank in settings.py no delete functionality enabled

[odscjames]

Slight issue here:

1. User A makes "proj"
2. User Admin deletes "proj"
3. User B makes "proj"
4. User A will still have in it's session that it's the admin of "proj" and will have admin access to "proj"

The way to solve this is that when the project is deleted, we should really go through ALL sessions and clear that name out wherever we find it. But sessions aren't really designed for doing this and I'll bet there is no supported API to do this in Django. We could prob hack something but that is not appealing.

Or .... we just decide this is a total edge case and we don't care for now.