Colours! And minor tweaks.
- Moves all stylesheets to /css
- Adds default colour scheme for #28
- Cleans up preamble
- Changes breakpoint from `480px` (iPhone 4 height) to `586px` (iPhone 5 height) for #26
- Adds subsection numbers, inspired by http://css-tricks.com/numbering-in-style/
- Fancy footnotes too, assuming you're running my altered version of Civil Footnotes
- Remembered to style block quotes and site footer