public function merge(array $newConfig, array &$config)
    {
        foreach ($newConfig as $routeName => $routeInfo) {
            if (!isset($config[$routeName])) {
                $config[$routeName] = $this->newRoute($routeName, $routeInfo);
            }

            if (isset($routeInfo['child_routes'])) {
                if (!isset($config[$routeName]['child_routes'])) {
                    $config[$routeName]['child_routes'] = array();
                }

                $this->merge($routeInfo['child_routes'], $config[$routeName]['child_routes']);
            }
        }
    }