Use nginx to serve website and other services

Instead of using multiple tunels to forward all our services to the VM
that serves jungle.bsc.es, just use nginx to redirect the traffic from
hut. This allows adding custom rules for paths that are not posible
otherwise.

Reviewed-by: Aleix Boné <abonerib@bsc.es>

m/hut/configuration.nix

@@ -17,6 +17,7 @@
     ./gitea.nix
     ./msmtp.nix
     ./postgresql.nix
+    ./nginx.nix
     #./pxe.nix
   ];