How can I add go to the next slide in impress.js
<p>impress.js is a new web presentation written using Javascript. I want to create custom events to go to the next page. For example, I might create a "Next" and "Previous" button.</p>

<p>The entire impress.js file is a function, calling <code>selectPrev();</code> from within the function will go to the next page. However, I'm not very good with Javascript, I don't know how to call <code>selectPrev();</code> from outside the function.</p>

<p>The file can be found here: <a href="https://github.com/bartaz/impress.js/blob/master/js/impress.js" rel="nofollow">https://github.com/bartaz/impress.js/blob/master/js/impress.js</a></p>
