Charisma nested accordion menu

gistfile1.html

<li class="accordion">
    <a href="#"><i class="glyphicon glyphicon-plus"></i><span> Accordion Menu</span></a>
    <ul class="nav nav-pills nav-stacked">
        <li><a href="#">Child Menu 1</a></li>
        <li class="accordion">
            <a href="#"><i class="glyphicon glyphicon-plus"></i><span> Accordion Menu</span></a>
            <ul class="nav nav-pills nav-stacked">
                <li><a href="#">Grand Child Menu 1</a></li>
                <li><a href="#">Grand Child Menu 2</a></li>
            </ul>
        </li>
    </ul>
</li>