title: Move selected items to top of listbox
body: <p>I am really going crazy over finding solution for showing selected items in listbox at top.
  I am using knockout here to bind my list box. The listbox is binded as below in my view</p>
  
  <pre><code>&lt;select id ="multiAltVersion" multiple="multiple"  data-bind="options:  $root.editOnlyAlternativeVersions,  optionsText: 'PlatformVersionName',optionsValue: 'Id',selectedOptions:  $root.copiedAltVersion, chosen: true  "&gt; &lt;/select&gt;
  </code></pre>
  
  <p>I call my WCF service to fill the listbox.</p>
  
  <pre><code>    function loadVersionListByProductType(prodtype) {
          var input =
          {
              ProductType: prodtype
  
          };
  
  
          $.ajax({
              url: "../RestService/Test/ReturnData",
              type: "PUT",
              contentType: 'application/json',
              processData: false,
              data: JSON.stringify(input),
              error: function (XMLHttpRequest, textStatus, errorThrown) {
                  alert(errorThrown);
              },
              success: function (allData) {
                  var mappedVersionListByProdType = $.map(allData, function (item) {
  
                      return new productVersionListByProductType(item);
                  });
                  self.editOnlyAlternativeVersions(mappedVersionListByProdType);
  
  
              }
  
          });
  
      }
  </code></pre>
  
  <p>When the data is returned from WCF service it returns data in descending order. But i want to show selected at top and then sort the list in descending manner. I get list of items from another service and selected items from another service. Does it make sense? How can i achieve it using Jquery?</p>