title: Simple Example to implement VS Code TreeDataProvider with JSON data
body: <p>I'm trying to add a <a href="https://code.visualstudio.com/api/extension-guides/tree-view" rel="noreferrer">Tree View</a> to my VS Code extension.
  Data is a complex JSON object. I stuggle to get this to working as the <a href="https://github.com/microsoft/vscode-extension-samples/tree/master/tree-view-sample" rel="noreferrer">examples</a> aren't straight forward to me.</p>
  
  <p>Lets say I have a simple object: </p>
  
  <pre class="lang-json prettyprint-override"><code>"cars": [
    { "name":"Ford", "models":[ "Fiesta", "Focus", "Mustang" ] },
    { "name":"BMW", "models":[ "320", "X3", "X5" ] }
  ]
  </code></pre>
  
  <p>I would like to render this in the treeview as follows:</p>
  
  <pre><code>Cars
   &gt; Ford
     &gt; Fiesta
     &gt; Focus
     &gt; Mustang
   &gt; BMW
     &gt; 320
     &gt; X3
     &gt; X5
  </code></pre>
  
  <p>Any pointers how to achieve this, or know of an repo I can look at that does something similar?</p>