feature(lib for bgs) adding a library for backgrounds

lib/theme/bgs.nix

@@ -0,0 +1,19 @@
+lib: {
+  bgs = rec {
+    files = {
+      wallpaper_1 = "~/media/images/bg_1.jpg";
+      wallpaper_2 = "~/media/images/bg_2.jpg";
+      wallpaper_3 = "~/media/images/bg_3.jpg";
+      wallpaper_4 = "~/media/images/waterwindow.jpg";
+      wallpaper_5 = "~/media/images/barngreet.png";
+    };
+
+    list = builtins.attrNames files;
+
+    resolve = name: if name == null then null else files.${name};
+
+    resolveList = names: builtins.filter (x: x != null) (map resolve names);
+
+    all = builtins.attrValues files;
+  };
+}

lib/theme/default.nix

@@ -0,0 +1,3 @@
+lib: {
+  inherit ((import ./bgs.nix lib)) bgs;
+}