public HttpResponseMessage Put(int id, [FromBody] Traveler traveler)
        {
            // returning 404 if the entity doesn't exist
            if (Travelers.GetSingle(id) == null)
            {
                return(Request.CreateResponse(HttpStatusCode.NotFound));
            }

            Travelers.Edit(traveler);
            Travelers.Save();
            return(Request.CreateResponse(HttpStatusCode.OK));
        }
        public HttpResponseMessage Delete(int id)
        {
            var reservation = Travelers.GetSingle(id);

            // returning 404 if the entity doesn't exist
            if (reservation == null)
            {
                return(Request.CreateResponse(HttpStatusCode.NotFound));
            }

            Travelers.Delete(reservation);
            Travelers.Save();
            return(Request.CreateResponse(HttpStatusCode.OK));
        }
        //[HttpPost]
        //public HttpResponseMessage RegisterForNotifications
        //    ([FromBody]RegisterNotificationsRequest request)
        //{
        //    var traveler = Travelers.FindBy(t => t.TravelerUserIdentity == request.DeviceID).SingleOrDefault();

        //    // Handling the HTTP status codes
        //    if (traveler == null)
        //    {
        //        return Request.CreateResponse(HttpStatusCode.NotFound);
        //    }
        //    else
        //    {
        //        WNSManager.RegisterDevice(request.DeviceID, request.DeviceURI);
        //        return Request.CreateResponse(HttpStatusCode.Created, request);
        //    }
        //}

        public HttpResponseMessage Post([FromBody] Traveler traveler)
        {
            // saving the new order to the database
            Travelers.Add(traveler);
            Travelers.Save();

            AddInitialData(traveler);

            // creating the response, with three key features:
            // 1. the newly saved entity
            // 2. 201 Created status code
            // 3. Location header with the location of the new resource
            var response = Request.CreateResponse(HttpStatusCode.Created, traveler);

            response.Headers.Location = new Uri(Request.RequestUri, traveler.TravelerId.ToString());
            return(response);
        }