New home page

Fixes #70. This should be merged after #293.

- [x] Desktop styles
- [x] Tablet styles
- [x] Mobile styles
- [x] Test in IE 8 - 11
- [ ] Fix HTML linter issues
- [ ] Fix media queries in IE 8
We're doing it so that the dev assets work right out of the box. We should reconsider that strategy though.