Updates

  - Added FastClick activator
  - New Sass variable `$body-color`
  - Updated most Sass modules
  - Added Sass table module
  - `config.json` is now `.headstartrc`
  - Added demo partial for general styling
  - `layout/header.html` is now `layout/layout-top.html`, while
`layout/footer.html` is now `layout/layout-bottom.html. This to prevent
confusion with possible partials `header` and `footer`.