reenable definition links in no-js version
redesign of TOC title
make the TOC toggle button smaller and add retina support
TOC header type tweaks
simplify layout structure
account for simpler layout in media queries and expand size of definitions on small screens
bring back the open definitions header
improvements to open defs and now working on iPads
more TOC title spacing tweaks
Merge remote-tracking branch 'upstream/master'
Merge pull request #221 from ascott1/master

Layout and design improvements