Move common nix code one level up.

common/user-node.nix

@@ -0,0 +1,12 @@
+{ pkgs, inputs, ... }:
+{
+  imports = [
+    # not used for this profile but defines options used by the other imports
+    inputs.impermanence.nixosModules.impermanence
+    ./cifs-client.nix
+    ./consul.nix
+    ./glusterfs-client.nix
+    ./sshd.nix
+    ./user-ppetru.nix
+  ];
+}