public function cdn($name, $url, $type = null)
    {
        // Check if there is a type provided
        if($type === null)
        {
            // No type provided, so derive it
            $type = substr(strrchr($url, '.'), 1);
        }

        // Grab the CDN group
        $group = config('assetprocessor.attributes.group.cdn', 'cdn');

        // Add the asset type
        $this->files[$type][$group][$name] = $url;
    }