title: Bootstrap UI - How can I change the accordion header icon, on tab expanded?
body: <p>How can I change the accordion header icon, on tab expanded ?</p>
  
  <p>Accordion plunke URL is : <a href="http://plnkr.co/edit/7HMhoHk9AWyBAHALgD0P?p=preview" rel="nofollow">http://plnkr.co/edit/7HMhoHk9AWyBAHALgD0P?p=preview</a></p>
  
  <pre><code> &lt;accordion-group&gt;
          &lt;accordion-heading&gt;
              I can have markup, too! &lt;i class="icon-check"&gt;&lt;/i&gt;
          &lt;/accordion-heading&gt;
          This is just some content to illustrate fancy headings.
      &lt;/accordion-group&gt;
    &lt;/accordion&gt;
  </code></pre>
  
  <p>So basically I want to change the icon-check class  to let's say icon-uncheck, when the  tab is expanded</p>