Bind mount /home as /nfs/home in apex and owls

Fixes: #232
Reviewed-by: Rodrigo Arias Mallo <rodrigo.arias@bsc.es>

m/apex/configuration.nix

@@ -7,6 +7,7 @@
     ../module/ceph.nix
     ../module/hut-substituter.nix
     ../module/slurm-server.nix
+    ../module/nfs-home-bind.nix
     ./nfs.nix
     ./wireguard.nix
   ];

m/module/nfs-home-bind.nix

@@ -0,0 +1,8 @@
+{
+  # Alias nfs home
+  fileSystems."/nfs/home" = {
+    device = "/home";
+    fsType = "none";
+    options = [ "bind" ];
+  };
+}

m/owl1/configuration.nix

@@ -9,6 +9,7 @@
     ../module/slurm-firewall.nix
     ../module/debuginfod.nix
     ../module/hut-substituter.nix
+    ../module/nfs-home-bind.nix
   ];
 
   # Select the this using the ID to avoid mismatches

m/owl2/configuration.nix

@@ -9,6 +9,7 @@
     ../module/slurm-firewall.nix
     ../module/debuginfod.nix
     ../module/hut-substituter.nix
+    ../module/nfs-home-bind.nix
   ];
 
   # Select the this using the ID to avoid mismatches