Bugfix: crate will always know if it's on a TargetField or not

src/killer_sokoban/Crate.java

@@ -4,6 +4,7 @@ package killer_sokoban;
 public class Crate extends Moveable {
 	
 	private boolean isOnTarget;
+	private int onTargetTimes = 0;
 	
 	
 	/**
@@ -19,6 +20,7 @@ public class Crate extends Moveable {
 	 */
 	public void stepOnTarget(Worker w)	{
 		w.incrementPoint();
+		onTargetTimes++;
 		isOnTarget=true;   
 	}
 	
@@ -27,7 +29,8 @@ public class Crate extends Moveable {
 	 */
 	public void stepOffTarget(Worker w)	{
 		w.decrementPoint();
-		isOnTarget=false;  
+		onTargetTimes--;
+		if(onTargetTimes == 0) isOnTarget=false;
 	}
 	
 	/** Ha a láda kapcsolóra került, akkor kerül meghívásra ez a függvény.