Add some meta-info to landing TOC page #29
Description
Right now, navigating to the homepage just gives you a TOC with no info or context.
It'd be good to have a mission statement / intro up top that details:
- What the site is
- What the site isn't
- How to navigate it
- Where to go for help / corrections (this repo!)
- Info about it being a living doc / constant WIP, contributions open, etc.