Shell/4202

Removed the sidebar from third party docs

This also uncovered some styling problems where our style sheets had the space for the sidebar hardcoded all over the place. So also did a large cleanup of our css, which is most of the commits here.

This drops the frame around the article content, which is something we didn't want anyway. Should be less visual bugs with the sidebar too.
[endlessm/eos-shell#4202]