A jQuery factory for creating sprites from images. Each sprite created
from a Sprite Factory is assumed to be the same size
Features
* Works from a rectuangluar grid of sprites.
* Fast, good for rendering large numbers of similar sprites
* Preloading CSS for large images (will add the 'loading' class to
the element until the image has been loaded)
* Can use transparent PNGS for IE6 and IE7
* Light mode, using half the number of elements (only suitable for
non-transparent images)
Demo => http://weepy.github.com/sprite-factory
Blog Post => http://blog.parkerfox.co.uk/2009/10/07/jquery-sprite-factory/
