protected function configure()
  {
    parent::configure();

    $this
        ->addOption(
            'host',
            NULL,
            InputOption::VALUE_OPTIONAL,
            'The host address to serve the application on.',
            'localhost'
            )
        ->addOption(
            'docroot',
            NULL,
            InputOption::VALUE_OPTIONAL,
            'Specify an explicit document root.',
            FALSE
        )
        ->addOption(
            'port',
            NULL,
            InputOption::VALUE_OPTIONAL,
            'The port to serve the application on.',
            8000
        );
  }