code: public function minionError(\Exception $ex, $code) {
          $handler = new ExceptionHandler($this['debug']);
          $exception = FlattenException::create($ex);
          $response = Response::create($handler->getHtml($exception), $code, $exception->getHeaders())
              ->setCharset(\ini_get('default_charset'))
          ;
  
          if($this['debug'])
              return $response;
          else {
              $content = <<<HTML
  <!DOCTYPE html>
  <html>
      <head><title>Error $code</title></head>
      <body><h1>Error {$exception->getMessage()} occured</h1></body>
  </html>
  HTML;
  
              if($this['minion.useTwig'] && isset($this['twig'])) {
                  $twig = $this['twig'];
                  $tpl = "Static/$code.html.twig";
                  if(!Utils::templateExists($twig, $tpl))
                      $content = \str_replace('%d', $code, $content);
                  else
                      $content = $twig->render($tpl, ['exception' => $ex]);
              } elseif(\file_exists($tpl = Utils::fixPath($this->getRootDir() . "/Static/$code.html.php")))
                  $content = Utils::renderPhpTemplate($tpl, ['exception' => $ex]);
  
              $response->setStatusCode($code);
              $response->setContent($content);
  
              return $response;
          }
      }
docs: @internal
  
  Handle errors and exceptions thrown by entire application.
  
  @param \Exception $ex   Any exception
  @param integer    $code HTTP status code
  
  @return Response Response to the client with nice error page