title: Callback event when jQuery 'mmenu' opened
body: <p>Using the jQuery <a href="http://mmenu.frebsite.nl/">mmenu plugin</a> I need to call a JavaScript function after the menu has finished opening.  I can't see from the <a href="http://mmenu.frebsite.nl/documentation/api.html">API documentation</a> how to do this using the plug-in API, so I'm thinking perhaps the only option is to observe the class name on the <code>&lt;html&gt;</code> element, which gains a class of <code>mm-opened</code> when the menu is opened.  This feels a little 'hacky' though, so I wondered if anyone could see a way, within the bounds of the native API, to accomplish the required function call?</p>
  
  <p>EDIT: Contrary to expectations the <code>openPanel</code> event doesn't fire when the menu is opened - it only fires when sub-menus are opened, so although this suggests it would do the job, it doesn't.</p>
  
  <p>Many thanks.</p>