public void SendNotification(string message, int?badge, IEnumerable <string> deviceTokens)
 {
     using (var pushClient = new PushServiceClient())
     {
         pushClient.EnqueueNotification(
             CoreContext.TenantManager.GetCurrentTenant().TenantId,
             SecurityContext.CurrentAccount.ID.ToString(),
             PushNotification.ApiNotification(message, badge),
             deviceTokens.ToList());
     }
 }