check link

check.js

function check(link) {
  var errorMessage = 'Mumble mumble... this seems to be an invalid link! :(';
  return new Promise(function(resolve, reject) {
    try {
      http.request(link, function(res) {
        debug('link status is ', res.statusCode);
        if (res.statusCode !== 404) {
          resolve(link);
        } else {
          reject(errorMessage);
        }
      }).end();
    } catch(ex) {
      reject(errorMessage);
    }
  });
}