Show group ownership details in read only group view.

This patch:

- Adds a "Group Ownership" column in the read only view
  of a group page
- Indicates if a group's members have been populated from LDAP

Bug: 990860

Show the group owners first.

The rest of the bug has already been fixed in an earlier
commit.

Change-Id: I867a3338fa57c12e6b8b7829e4754d27e35d9c3c