public async Task UpdateStatus(int travelrequestId, TravelRequestStatus status, string comments)
        {
            var travelRequest = await _travelRequestRepository.GetAsync(travelrequestId);

            if (travelRequest != null)
            {
                travelRequest.Status = status;
                if (!string.IsNullOrWhiteSpace(comments))
                {
                    if (!string.IsNullOrEmpty(travelRequest.Comments))
                    {
                        travelRequest.Comments = String.Format("{0}{1}{2}", travelRequest.Comments, System.Environment.NewLine, comments);
                    }
                    else
                    {
                        travelRequest.Comments = comments;
                    }
                }
                await _travelRequestRepository.UpdateAsync(travelRequest);

                if (travelRequest.Status == TravelRequestStatus.Approved)
                {
                    TravelsNotificationHub.NotifyApproved(travelRequest);
                }
                await _notificationService.EmailNotifyStatusChange(travelRequest, comments);
            }
        }
        /// <summary>
        /// <see cref="MyCompany.Travel.Client.ITravelRequestService"/>
        /// </summary>
        /// <param name="travelRequestId"><see cref="MyCompany.Travel.Client.ITravelRequestService"/></param>
        /// <param name="status"><see cref="MyCompany.Travel.Client.ITravelRequestService"/></param>
        /// <param name="comments"><see cref="MyCompany.Travel.Client.ITravelRequestService"/></param>
        /// <returns><see cref="MyCompany.Travel.Client.ITravelRequestService"/></returns>
        public async Task UpdateStatus(int travelRequestId, TravelRequestStatus status, string comments)
        {
            string url = String.Format(CultureInfo.InvariantCulture
                                       , "{0}api/travelrequests/update?travelRequestId={1}&status={2}&comments={3}", _urlPrefix, travelRequestId, (int)status, comments);

            await base.GetAsync(url);
        }