private function registerFileConfig()
    {
        $this->app->singleton('config', function ($app) {
            $loader = $app->make('Concrete\Core\Config\FileLoader');
            $saver = $app->make('Concrete\Core\Config\FileSaver');

            return $app->build('Concrete\Core\Config\Repository\Repository', array($loader, $saver, $app->environment()));
        });
    }