function GravityWell(centerPoint, force, life, easing) {
      var _this;
      _this = _Behaviour.call(this, life, easing) || this;
      _this.distanceVec = new Vector2D();
      _this.centerPoint = Util.initValue(centerPoint, new Vector2D());
      _this.force = Util.initValue(_this.normalizeValue(force), 100);
      _this.name = "GravityWell";
      return _this;
    }
@memberof! Proton#
@augments Behaviour
@constructor
@alias GravityWell

@param {Vector2D} [centerPoint=new Vector2D] The point in the center
@param {Number} [force=100]					The force
@param {Number} [life=Infinity]				this behaviour's life
@param {String} [easing=easeLinear]	this behaviour's easing

@property {String} name The Behaviour name