title: Set Semantic-UI dropdown selected using array or string
body: <p>The snippet is what i got, by setting set selected 1 by 1 manually it work.
  But i want to do it programmatically like passing a string or an array that contain <code>["2", "3", "4"]</code> to the <code>set selected: array</code> or any other way i can insert an array i receive from ajax.</p>
  
  <p><div class="snippet" data-lang="js" data-hide="false" data-console="true" data-babel="false">
  <div class="snippet-code">
  <pre class="snippet-code-js lang-js prettyprint-override"><code>$('.ui.dropdown').dropdown('set selected', ["1", "2"]);</code></pre>
  <pre class="snippet-code-html lang-html prettyprint-override"><code>&lt;script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"&gt;&lt;/script&gt;
  &lt;link href="https://cdnjs.cloudflare.com/ajax/libs/semantic-ui/2.3.0/semantic.min.css" rel="stylesheet"/&gt;
  &lt;script src="https://cdnjs.cloudflare.com/ajax/libs/semantic-ui/2.3.0/semantic.min.js"&gt;&lt;/script&gt;
  &lt;select multiple class="ui dropdown" name="event"&gt;
      &lt;option value=""&gt;Select Service&lt;/option&gt;
      &lt;option value="1"&gt;opt 1&lt;/option&gt;
      &lt;option value="2"&gt;opt 2&lt;/option&gt;
      &lt;option value="3"&gt;opt 3&lt;/option&gt;
      &lt;option value="4"&gt;opt 4&lt;/option&gt;
      &lt;option value="5"&gt;opt 5&lt;/option&gt;
  &lt;/select&gt;</code></pre>
  </div>
  </div>
  </p>
  
  <p>I also tried using Remote Content as below, but the <code>selected</code> doesn't seem to work.</p>
  
  <p>json output:</p>
  
  <pre><code>"success": true,
  "results": [
    {
      "name"  : "Choice 1",
      "value" : "value1",
      "selected" : true
     }
  </code></pre>
  
  <p>Read the Remote content:</p>
  
  <pre><code> $('.ui.dropdown.state').dropdown({
    apiSettings: {
       url: '//api.semantic-ui.com/tags/{query}'
    },
     filterRemoteData: false
  }); `
  </code></pre>