code: function relayEvents(listener, emitter, events) {
    events.forEach(eventName => listener.on(eventName, event => emitter.emit(eventName, event)));
  }
docs: Relays events for a given listener and emitter
  
  @param {EventEmitter} listener the EventEmitter to listen to the events from
  @param {EventEmitter} emitter the EventEmitter to relay the events to