title: DevExtreme dxForm nested data datafield not working
body: <p>im having a datasource like this :</p>
  <pre><code>var data = [{
  &quot;name&quot; : &quot;jeff&quot;,
  &quot;house&quot;: {
     &quot;size&quot; : &quot;big&quot;,
     &quot;color&quot; : &quot;black&quot;
  }]
  </code></pre>
  <p>and i want the dxForm to be able to do :</p>
  <pre><code>formElement.dxForm({
    formData: data,
    items:  [{
       dataField : &quot;name&quot;
    },{
       dataField : &quot;house.size&quot;
    }]
   ...
  )};
  </code></pre>
  <p>i know this should work because it works with basicly all DevExtreme controls...</p>
  <p>am i missing something ?</p>
  <p>The DevExtreme Questions dont realy answer me, most people kinda figuered it out but on other frameworks and have other problems with it.</p>