Cinny includes nginx configuration which does URL rewrites now, as seen
here: https://raw.githubusercontent.com/cinnyapp/cinny/dev/docker-nginx.conf

That said, we have our own nginx configuration for Cinny, because we'd
like to run ngin as non-root and on a non-privileged port (80 -> 8080).

For this reason, we override `/etc/nginx/nginx.conf` and need to
duplicate what we see in `/etc/nginx/conf.d/default.conf` with our own
`server` block (which listens on port 8080).