Update docs & website to reflect Netlify as recommended hosting provider

[timwis]

With GitHub/GitLab pages as an equally viable option (but without the Editor UI), and self-hosting as a third option, for advanced users.

See #204 for discussion.

[timwis]

Having some trouble getting the Deploy to Netlify button working using this URL:

https://app.netlify.com/start/deploy?repository=https://github.com/timwis/jkan&branch=netlify-deploy&stack=cms

The issues are:

• It's not detecting that it's a Jekyll site, and instead runs npm run build as the build command (despite the netlify.toml)
• The fork it creates (technically a copy), is empty. This may have to do with the github actions workflow according to this thread. I've posted there asking for assistance.

[timwis]

Okay, I've managed to get it working on Netlify (I was stumped by a dependency issue for a few days). Just need to get the login working out-of-the-box and figure out why Netlify still thinks it's a JavaScript site and not a Jekyll one.