code: function(id) {
              var oldId = this.getId();
  
              Kinetic._removeId(oldId);
              Kinetic._addId(this, id);
              this._setAttr(ID, id);
              return this;
          }
docs: set id
  @method
  @memberof Kinetic.Node.prototype
  @param {String} id
  @returns {Kinetic.Node}