home: create 'modules/home' folder

Consolidating all modules under the same path, to clear out the
top-level directory.

modules/home/default.nix

@@ -0,0 +1,56 @@
+{ ... }:
+{
+  imports = [
+    ./aliases
+    ./atuin
+    ./bat
+    ./bitwarden
+    ./bluetooth
+    ./calibre
+    ./comma
+    ./dircolors
+    ./direnv
+    ./discord
+    ./documentation
+    ./feh
+    ./firefox
+    ./flameshot
+    ./fzf
+    ./gammastep
+    ./gdb
+    ./git
+    ./gpg
+    ./gtk
+    ./htop
+    ./jq
+    ./mail
+    ./mpv
+    ./nix
+    ./nix-index
+    ./nixpkgs
+    ./nm-applet
+    ./packages
+    ./pager
+    ./power-alert
+    ./secrets
+    ./ssh
+    ./terminal
+    ./tmux
+    ./udiskie
+    ./vim
+    ./wm
+    ./x
+    ./xdg
+    ./zathura
+    ./zsh
+  ];
+
+  # First sane reproducible version
+  home.stateVersion = "20.09";
+
+  # Who am I?
+  home.username = "ambroisie";
+
+  # Start services automatically
+  systemd.user.startServices = "sd-switch";
+}