code: function (events) {
    // store events
    this.events = events;
  
    // placeholder for the webdriver server port & host
    this.port = null;
    this.host = null;
  
    // configure express
    this.app = express();
  
    this.app.use(connect.json());
    this.app.use(connect.urlencoded());
  
    // load the commands
    this._loadCommands();
  }
docs: Firefox Autotest (Marionette)
  WebDriver handler & request executor
  
  @module FirefoxDriver
  @class WebDriverServer
  @namespace FirefoxDriver
   
  Configures the express server
  Prepares the object properties
  Loads the webdriver commands
  
  @constructor
  @param {EventEmitter} events