protected function mergeIncludes(&$config)
    {
        if (!empty($config['includes'])) {
            foreach ($config['includes'] as $path) {

                // Don't load the same files more than once
                if (!array_key_exists($path, $this->loadedFiles)) {
                    $this->loadedFiles[$path] = true;
                    $config = array_merge_recursive($this->load($path), $config);
                }
            }
            unset($config['includes']);
        }
    }