Meeting Permissions tab

[edemaine]

I'd like to add a tab in the left border (next to Meeting Rooms) called Meeting Permissions (or drop "Meeting" from both).

• Initially locked to editing just by the creator (which is problematic if you reset presenceId by reloading before logging in).
• Who can edit the meeting title?
• Who can create new rooms?
• Who can create new tabs in rooms? (e.g. temporarily for lecturing, as originally raised in Turn off tab creation temporarily #44)
• Who can edit tabs?
• Which tab types to allow / show in New Tab menu? (e.g. disable Zoom)
• Who can archive rooms?
• Who can see/enter/unarchive archived rooms? [Srini]
• Who can control these settings (admin)?
• User list for blessing into staff/etc. roles
• Perhaps configurable list of roles?
• Default role for new users
• Default role for anonymous users, including "no access, require login"
• Allowed login mechanisms (e.g. Shimmer, Comingle, ...)
• Cap on # students in a room [Srini]
• Cap number of rooms a student is in [Srini]
• Default sort (and who can edit it?) -- currently requires database access

Some of these items would also like to have room-level permissions. For example:

• Who can create new tabs in this room?
• Who can edit new tabs in this room?

(blocked on #53)