title: Playframework scala helper for select input with optgroup
body: <p>Is in playframework scala helper to achive optgroup in input select?</p>
  
  <p>Example: </p>
  
  <pre><code> http://jsfiddle.net/g4ffzvs8/
  </code></pre>
  
  <p>Code:</p>
  
  <pre><code>&lt;select style="width:300px" id="source"&gt;
                 &lt;optgroup label="Alaskan/Hawaiian Time Zone"&gt;
                     &lt;option value="AK"&gt;Alaska&lt;/option&gt;
                     &lt;option value="HI"&gt;Hawaii&lt;/option&gt;
                 &lt;/optgroup&gt;
                 &lt;optgroup label="Pacific Time Zone"&gt;
                     &lt;option value="CA"&gt;California&lt;/option&gt;
                     &lt;option value="NV"&gt;Nevada&lt;/option&gt;
                     &lt;option value="OR"&gt;Oregon&lt;/option&gt;
                     &lt;option value="WA"&gt;Washington&lt;/option&gt;
                 &lt;/optgroup&gt;
                &lt;/select&gt;
  </code></pre>