[New: openFATE 309067] Stabelize group handling

Feature added by: Adrian Schröter (adrianSuSE) Feature #309067, revision 1 Title: Stabelize group handling Buildservice: Candidate Priority Requester: Mandatory Projectmanager: Important Requested by: Adrian Schröter (adriansuse) Description: The user management allow also to use groups for permission settings. However, the current implementation is not yet finished. This feature is about to complete it and to allow group permission handling for * attribute settings * request and review handling -- openSUSE Feature: https://features.opensuse.org/309067