title: Add class to timezone select box in CodeIgniter
body: <p>By doing <code>&lt;?php $this-&gt;load-&gt;helper('date'); echo timezone_menu('UM8'); ?&gt;</code> I can get a bunch
  of helpful timezone options in a select box from CI which generated as:</p>
  
  <pre><code>&lt;select name="timezones"&gt;
     &lt;option value="UM12"&gt;(UTC -12:00) Baker/Howland Island&lt;/option&gt;
     &lt;option value="UM11"&gt;(UTC -11:00) Samoa Time Zone, Niue&lt;/option&gt;
     ...
  &lt;/select&gt;
  </code></pre>
  
  <p>However, I want to add a class (for example, <code>&lt;select name="timezones" class="form-control"&gt;</code>) to that select box to inherit style from Bootstrap3. Anyone knows how to do this?</p>