[IMPLEMENTED] Permission for forum admins / global moderators to modify group roles


There are permissions available for forum admins and global moderators to let them change most things within all social groups, but there's still no permission to change the roles of members within a social group.

It would be useful for the moderation staff of the overall forums to be able to promote/demote roles of group members. This would allow them to add a new group admin in place of an inactive existing group admin, or demote problematic people from group admin/moderator roles, or remove certain members from a group, etc.
If the ability to remove or edit group bans is added, there would hopefully also be a way for forum moderation staff to be able to manage group bans as well.