add colmena function

lib/colmena.nix

@@ -0,0 +1,26 @@
+{ inputs, overlays }:
+let
+  inherit (builtins) mapAttrs;
+in {
+# From https://github.com/otavio/nix-config/blob/master/lib/default.nix
+  mkColmenaFromNixOSConfigurations = nixosConfigurations:
+    {
+      meta = {
+        description = "Pyrox's Deployments";
+        nixpkgs = import inputs.nixpkgs {
+          system = "x86_64-linux";
+          inherit overlays;
+        };
+
+        specialArgs = {
+          inherit inputs;
+        };
+      };
+    } // mapAttrs
+      (name: value:
+        {
+          nixpkgs.system = value.config.nixpkgs.system;
+          imports = value._module.args.modules;
+        })
+      nixosConfigurations;
+}