Modified Connection to accommodate multiple ConnectionListeners
- Implemented first version of GameRule checking
Merge remote-tracking branch 'origin/master' into gamelogic-sprint4
Fixed order of ConnectionHandler to avoid NullPointerException
-Updated Network Recovery in GameState. 
-Added BLOCKED State to PlayerState for communication in case of network
interruption with GUI.
Updated class diagram
Merge remote-tracking branch 'origin/gamelogic-sprint4' into sprint4-network
Made GameRule Serializable, moved code out of try/catch block
Merge remote-tracking branch 'origin/gui-sprint5'
Merge remote-tracking branch 'origin/gamelogic-sprint4'
Merge remote-tracking branch 'origin/sprint4-network'