PurchasableCircularList, StationCircularList:
Changed sameOwnerCheck to void.
Fix sameOwnerCheck

PurchasableCircularList:
Add getGroupMembers() method
Add + Implement playerPropertiesDetails()
This is a basic method for the cui which will display all needed information about the property of the player.
Also there is the not yet implemented method groupDetails() which will show all needed information regarding the Group the Purchasable is in.