Player is now floating between dimensions if the exit of the other stargate is blocked

also fixes #7

cicaprojekt/Wall.java

@@ -44,6 +44,7 @@ public class Wall extends Tile {
     }
 
     public void onExit(PlayerBase playerBase) throws IllegalStateException {
+        if(sg != null) return;
         throw new IllegalStateException("Hiba! Te hogy kerültél a falba?");
     }