protected function loadConfiguration(Container $app)
 {
     $app->register(new ConfigServiceProvider(), ['config.paths' => [$app->getPath('config')]]);
     // First we will see if we have a cache configuration file. If we do, we'll load
     // the configuration items from that file so that it is very quick. Otherwise
     // we will need to spin through every configuration file and load them all.
     if (file_exists($cached = $app->getPath('cache') . 'config.php')) {
         $items = (include $cached);
         $app['config']->set($items);
         return true;
     }
     if (file_exists($app->getPath('env'))) {
         $app['config.loader']->load($app->getPath('env'));
     }
     $app['config.loader']->load([$app->getPath('config')], true);
 }