added move

src/Worm.java

@@ -151,4 +151,27 @@ public class Worm {
         this.maxPoints = (int) Math.round(maxPoints);
         setPoints(this.points);
     }
+    
+    /**
+     * 
+     * @param NumberSteps
+     * 
+     * @post ...
+     * 		|new.CoordX = CoordX + NumberSteps * distanceX
+     * 
+     * @post 
+     * 		|new.CoordY = CoordY + NumberSteps * distanceY
+     * 
+     * @throws IllegalArgumentException
+     * 		when the total of steps is lower then zero  
+     * 		|NumberSteps < 0
+     */
+    public void move(int NumberSteps) {
+    	if (NumberSteps < 0)
+    		throw new IllegalArgumentException();
+    	double distanceX = getRadius() * Math.cos(getOrientation());
+    	double distanceY = getRadius() * Math.sin(getOrientation());
+    	setCoordX(getCoordX() + NumberSteps * distanceX);
+    	setCoordY(getCoordY() + NumberSteps * distanceY);
+    }
 }