When you have admin-level access and you go to a group page of which you are a member, the web client would report that you were an administrator of the group, even if you were not.  It now tells what access level you have AND that you have general admin privileges.  Also, when you promoted yourself, the top message was not changing.
Add a background color to the admin text for groups.
Merge pull request #444 from girder/group-administrator-text

Fixed showing group administrators