title: Kendo grid field value needs to be different than displayed text
body: <p>I have a grid in kendo with the following columns: </p>
  
  <pre><code>columns: [
  { field: "GroupId", hidden: true},
  { field: "Name", title: "Group Name"}, 
  { field: "Description", title: "Description"},
  { field: "Users.length", title: "Assigned Users" }]
  </code></pre>
  
  <p>The datasource has the schema: </p>
  
  <pre><code>schema: {
      model: {
          id: "GroupId",
          fields: {
              Name: {editable: true},
              Description: {editable: true},
              Users: {editable: false},
          }
      }
  }
  </code></pre>
  
  <p>My problem: I do not want Users to be editable, so it has the editable: false property. But this doesn't seem to be binding to my Users.length field. </p>
  
  <p>Which of the following is the correct/implementable approach to this? I'm new to kendo, so I've had no luck figuring this out on my own. </p>
  
  <ol>
  <li>Can I have the field name refer to Users, and the display value be Users.length?</li>
  <li>Can I bind the field in the schema to Users.length somehow?</li>
  </ol>