title: Get ACF from relationship field with Timber
body: <p>I'm using Advanced Custom Fields on a custom post type. On the homepage I have a relationship field to select one of the posts in the custom post type.</p>
  
  <p>Using Timber, I'm struggling to get the ACF fields for that relationship post into the Context. I can get the standard wordpress info like title and content, but not the ACFs.</p>
  
  <p>I think I need to use TimberPost, but haven't had any success so far. </p>
  
  <p>This is in my page template. In the view it just outputs all the standard WP stuff:</p>
  
  <pre><code>$context['featureRelationship'] = get_field('feature');
  </code></pre>
  
  <p>So I tried this, but I'm going wrong somewhere:</p>
  
  <pre><code>$context['featureRelationship'] = new TimberPost(get_field('feature'));
  </code></pre>
  
  <p>Appreciate any help, thanks</p>