code: function http(url, options) {
    return request(url, extend({}, this.options.http, options))
      .then(function(response) {
        if (!response.ok) throw response.status + '' + response.statusText;
        return response.text();
      });
  }
docs: HTTP request loader.
  @param {string} url - The url to request.
  @param {object} options - An options hash.
  @return {Promise} - A promise that resolves to the file contents.