Redesign homepage to use touch icon, include site name as text

Looks like this now:

![redesigned front page](https://f.cloud.github.com/assets/449006/1950096/9a10c8e2-8134-11e3-86d3-223c9fb6edc0.png)

Could probably still be tweaked a bit more, but it's better than what we have now. It'd probably be a good idea to fetch the icons ourselves and combine them into a single sprite so we don't spam the CDN as a next step.