public function addDefaultFTPDownloaders(FTPWrapper $wrapper)
    {
        $this->addVotable(new FTPDownloader\FileDownloader($wrapper));
        $this->addVotable(new FTPDownloader\ResourceDownloader($wrapper));
        $this->addVotable(new FTPDownloader\NbFileDownloader($wrapper));
        $this->addVotable(new FTPDownloader\NbResourceDownloader($wrapper));
    }