* Creates an instance of a resolver class with a given command
*
* @param $controllerName The controller we shall resolve
* Creates an instance of a resolver class with a given command
*
* @param $controllerName The controller we shall resolve
* @return $resolverInstance The prepared controller resolver instance
* @throws EmptyVariableException Thrown if default command is not set
* @throws InvalidControllerException Thrown if default controller is invalid
*/
* @return $resolverInstance The prepared controller resolver instance
* @throws EmptyVariableException Thrown if default command is not set
* @throws InvalidControllerException Thrown if default controller is invalid
*/