machines: rename to 'hosts/nixos'

This will be more consistent in the future if I want to introduce darwin
or home-manager configurations.

hosts/nixos/aramis/default.nix

@@ -0,0 +1,29 @@
+# Edit this configuration file to define what should be installed on
+# your system.  Help is available in the configuration.nix(5) man page
+# and in the NixOS manual (accessible by running ‘nixos-help’).
+
+{ ... }:
+
+{
+  imports = [
+    ./boot.nix
+    ./hardware.nix
+    ./home.nix
+    ./networking.nix
+    ./profiles.nix
+    ./programs.nix
+    ./services.nix
+    ./sound.nix
+  ];
+
+  # Set your time zone.
+  time.timeZone = "Europe/London";
+
+  # This value determines the NixOS release from which the default
+  # settings for stateful data, like file locations and database versions
+  # on your system were taken. It‘s perfectly fine and recommended to leave
+  # this value at the release version of the first install of this system.
+  # Before changing this value read the documentation for this option
+  # (e.g. man configuration.nix or on https://nixos.org/nixos/options.html).
+  system.stateVersion = "20.09"; # Did you read the comment?
+}