boxshroud fixes

src/engine/net/client/ClientMessagePump.java

@@ -1888,6 +1888,14 @@ public class ClientMessagePump implements NetMsgHandler {
                     break;
                 case LEAVEREQUEST:
                     origin.disconnect();
+                    ArrayList<PlayerCharacter> sameMachine = new ArrayList<>();
+                    for (PlayerCharacter pc : SessionManager.getAllActivePlayers()) {
+                        if(origin.machineID.equals(pc.getClientConnection().machineID))
+                            sameMachine.add(pc);
+                    }
+                    if(sameMachine.isEmpty() == false){
+                        sameMachine.get(0).isBoxed = false;
+                    }
                     break;
                 case POWER:
                     PowersManager.usePower((PerformActionMsg) msg, origin, false);