- Remove no longer needed `acme-challenge` file
- Set title, description, social image, logo, etc. for SEO
- Use extensionless permalinks (old links still work)
- Cleanup `_config.yml`
- Import latest `_layouts/base` from https://brew.sh
Unfortunately there's no easy way to share this code with the brew.sh
site but it's at least able to have the `css/`, `img/` (root) and
`_layouts` directories in sync between the two repositories.
Some small CSS tweaks were needed to make these pages render more
attractively.
GitHub now nicely generates a documentation site for us at
http://brew.sh/brew based on our docs folder. Optimise the output of
this and the GitHub docs directory for readability and the various user
groupings.
