SeatGuard bug fixes.
SeatGuard bug fixes.

- Fix 2 cases where SeatGaurd was not aware of the fact that
  groups may exist without actual permissions.
- Fix a potential bug in calculating the 'superuser' privilege
  where calculations may stop as soon as a empty group with no
  permissions is found.

Krienas/seat,omgninjaz/seat,omgninjaz/seat,Krienas/seat,omgninjaz/seat,omgninjaz/seat