title: jsTree not rendering using AJAX
body: <p>I am trying to implement jsTree and AJAX to display a dynamic file structure on a server. I have the webpage setup as</p>
  
  <pre><code>&lt;div id="tree"&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>My Javascript is</p>
  
  <pre><code>    $(document).ready(function(){
  
          $('#tree').jstree({
              'core' : {
                  'data' : {
                      'url' : function(node) {
                          return 'folder/?folder=' + ((node.id === '#')?'':node.id);
                      },
                      'type': 'GET',
                      'dataType': 'json',
                      'contentType':'application/json',
                      'data' : function (node) {
                          return { 'id' : node.id };
                      }
                  }
              }
          });
      });
  </code></pre>
  
  <p>My Java endpoint returns a String in this JSON format.</p>
  
  <pre><code>[
      {
          "id":"ci/",
          "text":"ci",
          "parent":"#"
      },
      {
          "id":"dev/",
          "text":"dev",
          "parent":"#"
      },
      {
          "id":"prod/",
          "text":"prod",
          "parent":"#"
      }
  ]
  </code></pre>
  
  <p>When I put break-points in the javascript and the Java back, I see "url" function getting called first, then "data" function and then it goes to the back-end. It returns the String, but nothing happens. My  only shows "Loading..."</p>
  
  <p>I downloaded the jsTree from <a href="https://github.com/vakata/jstree/zipball/3.0.8" rel="nofollow">https://github.com/vakata/jstree/zipball/3.0.8</a> and I am including the two files from the zip</p>
  
  <pre><code>&lt;script src="${pageContext.request.contextPath}/js/vendor/jstree.min.js"&gt;&lt;/script&gt;
  &lt;link rel="stylesheet" href="${pageContext.request.contextPath}/css/style.min.css"&gt;
  </code></pre>
  
  <p>Ideally what I am trying to do is build out a folder tree structure that a user will eventually select the location for a file upload to S3. I want to lazy load the folders on click and the id will be the folder path (i.e. dev/en_US/someFolder/images/)</p>