Add vhost examples for popular reverse proxies

[pmaier1]

We should add some examples to use the stack behind a reverse proxy here. This is particularly important for Apache as that one needs specific config to work properly, namely

  ProxyPreserveHost on
  ProxyPass / http://127.0.0.1:8080/ nocanon
  ProxyPassReverse / http://127.0.0.1:8080/

[pmaier1]

Apache2 here #344

[pmaier1]

Nginx #486

[benbz]

#823 is a request for exposing this via Tailscale only, which is fairly closely related