title: Problem with methods when loading resources as a JSON feed
body: <p>I'm having problems using methods such as getResources and addResource when loading resources from a remote script containing a JSON feed.</p>
  <p>If the same resources are included as an array it works fine.
  Working example:</p>
  <pre><code>resources: [{&quot;id&quot;:&quot;a&quot;,&quot;title&quot;:&quot;Auditorium A&quot;},{&quot;id&quot;:&quot;b&quot;,&quot;title&quot;:&quot;Auditorium B&quot;,&quot;eventColor&quot;:&quot;green&quot;}....
  </code></pre>
  <p><a href="https://codepen.io/ProbablyTheRealJonas/pen/yLVzEJw" rel="nofollow noreferrer">https://codepen.io/ProbablyTheRealJonas/pen/yLVzEJw</a></p>
  <p>Not working:</p>
  <pre><code>resources: 'https://fullcalendar.io/demo-resources.json?with-nesting&amp;with-colors',
  </code></pre>
  <p><a href="https://codepen.io/ProbablyTheRealJonas/pen/BaQwVjY" rel="nofollow noreferrer">https://codepen.io/ProbablyTheRealJonas/pen/BaQwVjY</a></p>
  <p>What might I be missing?</p>