This makes use of my newly written adblocking DNS service, it does
assume that the server would have both wireguard and DNS enabled.
I would also like to move to using my ip-related library functions,
however it does not support IPv6 and is unlikely to be easily added...
But I am not sure that I *need* IPv6 support for my use-case.
Finally, I find this module a bit too heavy, it could be improved by
having specific 'server' and 'client' roles, instead of implicit roles
depending on whether an external IP exists.
Turns out the `wireguard` service isn't meant to be used for VPN-like
workflows (see [1]). and I'll probably have less trouble by using
`wg-quick` instead.
Nice bonus is that instead of having awfully named services running for
each peer, I only need the one service for `wg-quick` itself.
[1]: https://github.com/NixOS/nixpkgs/issues/51258
Bruno BELANYI