* @param $controllerName A controller name we shall look for
* @return $controllerInstance A loaded controller instance
* @throws InvalidControllerException Thrown if even the requested
* controller class is missing (bad!)
*/
* @param $controllerName A controller name we shall look for
* @return $controllerInstance A loaded controller instance
* @throws InvalidControllerException Thrown if even the requested
* controller class is missing (bad!)
*/