Pngsvg

I rebased the pngsvg branch which includes @BaconRanch's changes and made a few more. This PR supersedes PR #8.

A short summary:

* Added grunt support for development and deployment. Also combined and minified the css/js files reducing the size and number of http requests
* Converted the thumbnails to 8-bit saving 50%

TODO:

- [ ] Switch to jquery fancybox for the screenshots
- [ ] Fix media queries and responsive design
- [ ] Switch to normalize.css instead of reset.css
- [ ] Clean up style.css and fix issues like missing fallback colors etc. Also switch to hex colors when possible
- [ ] Move favicon to root