title: How to query the Wordpress API by ACF properties?
body: <p>I'm trying to query the Worpress API based on ACF properties.</p>
  
  <p>If I don't include a query, I get this output:</p>
  
  <pre><code>[{"id":215,"date":"2018-08-05T09:21:37","date_gmt":"2018-08-5T08:21:37","guid":{"rendered":"x"},"modified":"2018-08-05T09:21:37",
  "modified_gmt":"2018-08-05T08:21:37","slug":"sasradisson","status":"publish","type":"hotel","link":"https:x",
  "title":{"rendered":"SAS Radisson"},"template":"","acf":{"stad":{"value":"barcelona","label":"barcelona"},
  "description":"","images":false},"_links":{"self":[{"href":"x"}],"collection":[{"href":"x"}],
  "about":[{"href":"x"}],"wp:attachment":[{"href":"x"}],"curies":[{"name":"wp","href":"x","templated":true}]}},
  {"id":205,"date":"2018-08-04T11:25:35","date_gmt":"2018-08-04T10:25:35","guid":{"rendered":"x"},
  "modified":"2018-08-04T14:22:12","modified_gmt":"2018-08-04T13:22:12","slug":"citybox-oslo","status":"publish",
  "type":"hotel","link":"x","title":{"rendered":"Citybox Oslo"},"template":"",
  "acf":{"stad":{"value":"oslo","label":"oslo"},"description":"","images":false},
  "_links":{"self":[{"href":"x"}],"collection":[{"x"}],"about":[{"href":"x"}],"wp:attachment":[{"href":"x"}],
  "curies":[{"name":"wp","href":"x","templated":true}]}}]
  </code></pre>
  
  <p>(I replaced all urls with "x" for brevity)</p>
  
  <p>Among all other properties, there are ACF properties, like this:</p>
  
  <pre><code>"acf":{"stad":{"value":"barcelona","label":"barcelona"}
  </code></pre>
  
  <p>None of these queries work:</p>
  
  <pre><code>/wp-json/wp/v2/hotels?acf={stad:{value:%27barcelona%27}}
  
  /wp-json/wp/v2/hotels?acf.stad.value=barcelona
  </code></pre>
  
  <p>How do I build a correct URL query?</p>
  
  <p>If that isn't possible, what would be an alternate solution?</p>