Add flag serialization marker to CollisionGroup for engine bitmasks
Add flag serialization marker to CollisionGroup for engine bitmasks

space-wizards/space-station-14,space-wizards/space-station-14,space-wizards/space-station-14-content,space-wizards/space-station-14,space-wizards/space-station-14-content,space-wizards/space-station-14,space-wizards/space-station-14,space-wizards/space-station-14-content,space-wizards/space-station-14