Optimized images

Lossless-ly optimize all images contained in this repo using a [custom script](https://gitorious.org/fmarier-misc-scripts/user-scripts/source/optimize_images) which makes use of these open source tools:

* [Pngcrush](http://pmt.sourceforge.net/pngcrush/)
* [OptiPNG](http://optipng.sourceforge.net/)
* [AdvanceCOMP](http://advancemame.sourceforge.net/comp-readme.html)
* [Gifsicle](http://www.lcdf.org/gifsicle/)
* [Jpegoptim](http://www.kokkonen.net/tjko/projects.html)

About a 65% reduction in size overall.