title: Bootstrap-select does not toggle "open" class
body: <p>Check it out please -> <a href="http://jsfiddle.net/1hzxrpmk/" rel="noreferrer">FIDDLE</a></p>
  
  <p>I downloaded the source from <a href="http://silviomoreto.github.io/bootstrap-select/" rel="noreferrer">http://silviomoreto.github.io/bootstrap-select/</a>, I really have no idea why it's not toggling "open" class of ".dropdown-toggle"
  I can fix it by adding some messy scripts, but I prefer the plugin to work right.</p>
  
  <p>the HTML:</p>
  
  <pre><code>&lt;div class="number customdp"&gt;
  &lt;select class="simple-dropdown" name="number"&gt;
      &lt;option&gt;1&lt;/option&gt;
      &lt;option&gt;2&lt;/option&gt;
      &lt;option&gt;3&lt;/option&gt;
      &lt;option&gt;4&lt;/option&gt;
      &lt;option&gt;5&lt;/option&gt;
  &lt;/select&gt;
  </code></pre>
  
  <p></p>
  
  <p>does anybody have a solution ?</p>