Org members appear to have the ability to delete all rooms (any admin)

Created by: PWKad

I am a member of an organization on Github and it appears I have full rights to delete public and private rooms. This shouldn't be allowed or at least should be able to opt-out of. Only the admin of the org should be able to delete rooms, especially large public ones.

Ideas

New sd.admins: "GH_ORG_ADMIN" type

Add a new sd.admins type which only allows GitHub admins like GH_ORG_ADMIN. Currently those GitHub associated communities/rooms have sd.admins: "GH_ORG_MEMBER" or sd.admins: "GH_REPO_PUSH"

New Gitter role

Add a owner role which can only delete a room.

This also helps with the permissions issue so we can separate admin moderators from owners of the room