- Remove "demo", "production" containers and have just one.
- Remove dependency on config.toml and inline config to env vars.
- Have a single idempotent instal+upgrade+run command that eliminates
the need for manual upgrade steps.
- Remove `.sh` install scripts.
- Simplify and clean up install and update docs.
This commit merges the static website and docs that was on
https://github.com/knadh/listmonk-site repository into the main
listmonk repo.
It also adds a GitHub Actions workflow to public the sites on GitHub
Pages instead of Netlify.
