Issue #40: Cancel scroll on mouse wheel (Cont)

Ok had another think and a bit of research on this. I've added in the `touchmove` event for the smart phones, for the clicking on the scroll bars, the window counts this as a `mousedown` event, but this also means that clicking anywhere on the page will cancel the animation... not sure if this is a good thing? I've also added the `keydown` event as previously mentioned in the issue. 

Let me know what you think :)