Proof of concept: Simple red & self link CSS entry point

- Format red & self links using CSS only.
- Next steps:
    - store CSS & update it when linked pages are created or deleted
    - verify visual match with skin, use skin provided values instead of
      hardcoded styles
    - provide a JSON API for all / missing links as well for custom styling
    - get rid of ../ href prefix in Parsoid in subpages, use ./ and <base
      href> exclusively