title: Kendo UI: Update transport doesn't trigger after calling datasource sync
body: <p>Im struggling on this in hours now, I cant find a good documentation on how to implement simple ajax UPDATE on server using forms and Kendo MVVVM and datasource. </p>
  
  <p>KENDO MVVM</p>
  
  <pre><code>$(function() {
  
      var apiUrl = "http://a31262cd2f034ab8bcda22968021f3b8.cloudapp.net/api",            
          meetingDatasource = new kendo.data.DataSource({
              transport: {
                  read: {
                      url: apiUrl + "/meetings/4",
                      dataType: "jsonp"
                  },
                  update: {
                      type: "PUT",
                      url: apiUrl + "/meetings",
                      contentType: "application/json; charset=utf-8",
                      dataType: 'json',
                  },
  
                  parameterMap: function(options, operation) {
                      return kendo.stringify(options);
                  }
              },
              batch: true,
              change: function() {
              },
              schema: {
                  model: {
                      id: "Id",
                      fields: {
                          Title: { editable: true },
                          StartTime: { type: "date" },
                          EndTime: { type: "date" }
                      }
                  }
              }
          });
  
      meetingDatasource.fetch(function () {
  
          var viewModel = kendo.observable({
              description: result.Description,
              title: result.Title,
              venue: result.Location,
              startDate: result.StartTime,
              endDate: result.EndTime,
              saveChanges: function (e) {
  
                  //im not sure with this line
                  this.set("Title", this.Title);
                  meetingDatasource.sync();
  
                  e.preventDefault();
  
              }
          });
  
          kendo.bind($("#view"), viewModel);
      });
  
  });
  </code></pre>
  
  <p>THE UI</p>
  
  <pre><code>&lt;ul class="forms"  id="ul-meeting"&gt;
              &lt;li&gt;
                  &lt;label for="title" &gt;Title:&lt;/label&gt; 
                  &lt;input data-bind="value: title" class="k-textbox" style="width:350px;"/&gt;
              &lt;/li&gt;
              &lt;li&gt;
                  &lt;label for="description" &gt;Description:&lt;/label&gt; 
                  &lt;textarea data-bind="value: description"  id="description" rows="6" cols="80" class="k-textbox" style="width:350px;"&gt;&lt;/textarea&gt;
              &lt;/li&gt;
              &lt;li&gt;    
                  &lt;label for="location"&gt;Venue:&lt;/label&gt; 
                  &lt;textarea  data-bind="value: venue" id="location" rows="4" cols="80" class="k-textbox" style="width:350px;"&gt;&lt;/textarea&gt;
              &lt;/li&gt;
              &lt;li&gt;
                  &lt;p&gt;
                      &lt;label for="start-datetime"&gt;Start:&lt;/label&gt; 
                      &lt;input  data-bind="value: startDate" id="start-datetime" style="width:200px;" /&gt;
                  &lt;/p&gt;
                  &lt;p&gt;
                      &lt;label for="end-datetime"&gt;Finish:&lt;/label&gt; 
                      &lt;input data-bind="value: endDate"  id="end-datetime" style="width:200px;" /&gt;
                  &lt;/p&gt;
              &lt;/li&gt;
          &lt;/ul&gt;
  </code></pre>
  
  <p>The problem is, the TRANSPORT READ triggers but the TRANSPORT UPDATE never triggers even if I explicity call the Datasource.sync(). Is is something I am missing here?</p>