Quick stab at refactoring.

I've deferred handling resizes to the CSS, and gutted most of the current code. By doing so, I've reduced the code footprint, and addressed issues (#3) such as wrong scaling for the enlarged images. One might go further, and make it a jQuery plugin, but that would require a bit more scaffolding… which I'm not certain would be of interest. Consequently, it's a simple function with an optional parameter for setting the image class to add the effect to. Cheers. 

:thumbsup: