anchor.diff:    void move(String direction) {
       directionSystem.addToMainDirection(direction);
     }
  +  
  +  //TODO: make it work
  +  void moveBy(String direction, {int distance: 0}) {
  +
  +  }
  +  
  +  //TODO: make it work
  +  void moveTo(int x, int y) {
  +
  +  }
   
     /**
      * Stops the movement of the sprite.
  
positive.code:    * Defines where the sprite will move next.
     */
    bool advanceTime(num time) {
      
      _checkKillOutOfBounds();
  
      _checkCollideWorldBounds();
  
negative.code:     return true;
  
    }
  
    /**
     * Put the pivot point into the center of the sprite.
     */
  