title: Which class is added while sorting?
body: <p>As you know, on jQuery UI Dragable interaction, the element being dragged gets <code>.ui-draggable-dragging</code> class. Is there anything like this for sorting?</p>
  
  <p><a href="http://jsfiddle.net/teknoblogo/m6gWj/" rel="nofollow noreferrer">Example here</a>. I want to change element's background-color while dragging. Which class is added while element is dragging? <code>.ui-sortable-dragging</code>?</p>