Add print stylesheet

[matryer]

• Search bar shows up (useless once it's printed - I've tried it before, it just isn't the same)
• Title is Dox (/) not Dox - looks like Chrome adds the URL in brackets after links - solution would be to remove as many links as possible for print version
• Contents and Jump to... are overlapped on Chrome on Mac
• A few other odd artifacts appear on the printout
• Box around all content - unnecessary
• For big pages, would be great to have the toc printed at the top instead of behind a menu item.