Reset preview scroll position when post item is clicked

When scrolling through the preview of a long article, if the post was changed the scroll position of the preview would remain the same.

![ghostpreview](https://cloud.githubusercontent.com/assets/846587/3964791/7eb248d2-278d-11e4-80ce-6da126080df5.gif)

Good question, I may be misunderstanding but I presume you are referring to attaching the event handler to the `li` elements?

I could but I'd be attaching a new event handler to each li which incurs a small but noticeable performance cost. 

This uses event delegation and reduces the attached events by attach the event higher up the DOM and using event.target. I could probably optimise this further by attaching it to the `ul` rather than the `body` though