Allow complete deletion of groups.

Acceptance Criteria

Groups can be deleted simply and without problems. Initially, deletion should not have an audit trail and it should not be possible to undelete a group. Audit trail will become an objective (outside of this design doc) once the initial implementation is finished. In terms of the undelete operation it can be achieved by group re-creation under the original name.


Some hosts, especially those that are around for quite a long time, have many groups that are no longer used at all. There is currently no way to completely delete a group and that means that the host keeps an unnecessarily high number of refs. Also, it is a nuisance for the user to see so many different groups, when most of those are unused.