code: function (app, callback) {
      var appPath = pathExtra.resolve(npmHelpers.initialWd, app);
      var manifestPath = pathExtra.join(appPath, 'package.json');
  
      if (fs.existsSync(appPath) && fs.existsSync(manifestPath)) {
        fs.readFile(manifestPath, function checkError (err, manifest) {
          if (err) {
            logger.error(err);
            nodeHelpers.invoke(callback, err);
          } else {
            nodeHelpers.invoke(callback, err, JSON.parse(manifest), 'file');
          }
        });
      } else {
        var client = request.newClient('https://raw.githubusercontent.com/');
        /* Checking if a branch of the github repo is specified
         * within the application path parameter (separated with a @).
         */
        if (app.indexOf('@') > 1) {
          // if a branch is specified, we build the url with it.
          var manifestUrl = app.split('@')[0] + '/' + app.split('@')[1] +  '/package.json';
        } else {
          // if no branch is specified, we build the url with master branch.
          var manifestUrl = app + '/master/package.json';
        }
        console.log(manifestUrl);
  
        client.get(manifestUrl, function (err, res, manifest) {
          if (err) {
            logger.error(err);
            nodeHelpers.invoke(callback, err);
          } else if (res.statusCode !== 200) {
            logger.error(err);
            nodeHelpers.invoke(callback, err);
          } else {
            nodeHelpers.invoke(callback, err, manifest, 'url');
          }
        });
      }
    }
docs: Fetch application or plugin manifest from an url or a path
  
  @param {String} app App or Plugin name to fetch from url or path.
  @param {Function} callback Termination.