home: create 'modules/home' folder

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

modules/home/dircolors/default.nix

@@ -0,0 +1,15 @@
+{ config, lib, ... }:
+let
+  cfg = config.my.home.dircolors;
+in
+{
+  options.my.home.dircolors = with lib; {
+    enable = my.mkDisableOption "dircolors configuration";
+  };
+
+  config = lib.mkIf cfg.enable {
+    programs.dircolors = {
+      enable = true;
+    };
+  };
+}