filter out clusters without server groups in cluster nav
filter out clusters without server groups in cluster nav

sgarlick987/deck,kenzanlabs/deck,HaishiBai/deck,duftler/deck,zanthrash/deck-1,spinnaker/deck,sgarlick987/deck,icfantv/deck,ajordens/deck,ajordens/deck,duftler/deck,icfantv/deck,ajordens/deck,sgarlick987/deck,icfantv/deck,spinnaker/deck,zanthrash/deck-old,sgarlick987/deck,spinnaker/deck,HaishiBai/deck,icfantv/deck,duftler/deck,HaishiBai/deck,spinnaker/deck,zanthrash/deck-1,zanthrash/deck-1,zanthrash/deck-old,duftler/deck,ajordens/deck,kenzanlabs/deck,kenzanlabs/deck