code: function subclass$(obj,sup) {
  	for (var k in sup) {
  		if (sup.hasOwnProperty(k)) obj[k] = sup[k];
  	};
  	// obj.__super__ = sup;
  	obj.prototype = Object.create(sup.prototype);
  	obj.__super__ = obj.prototype.__super__ = sup.prototype;
  	obj.prototype.initialize = obj.prototype.constructor = obj;
  }
docs: helper for subclassing