public void UpdateTest()
 {
     var item = new Order {Id = "101"};
     var data = new Order
     {
         Name = "Test",
         CloseOrder = true
     };
     using (var server = new HttpServer(new RequestHandler
     {
         EstimatedMethod = "PUT",
         EstimatedPathAndQuery = string.Format("/v1.0/accounts/{0}/orders/101", Helper.AccountId),
         EstimatedContent = Helper.ToXmlString(data),
     }))
     {
         item.Update(data).Wait();
         if (server.Error != null) throw server.Error;
     }
 }