feat(scripts): add auc roman calendar

packages/scripts/auc.nix

@@ -0,0 +1,31 @@
+{ stdenv, fetchFromGitHub, lib, pandoc }:
+let
+  owner = "kamalist";
+in
+stdenv.mkDerivation rec {
+  pname = "auc";
+  version = "2019-04-02";
+
+  src = fetchFromGitHub {
+    inherit owner;
+    repo = "AUC";
+    rev = "66d1cd57472442b4bf3c1ed12ca5cadd57d076b3";
+    sha256 = "0gb4asmlfr19h42f3c5wg9c9i3014if3ymrqan6w9klgzgfyh2la";
+  };
+
+  installPhase = ''
+    mkdir -p $out/{bin,man/man1}
+    install auc $out/bin
+    ${pandoc}/bin/pandoc -V title=${lib.escapeShellArg pname} -V section=1 $src/README.md -s -t man -o $out/man/man1/auc.1
+  '';
+
+  meta = with lib; {
+    description = "Command-line Roman calendar";
+    longDescription = ''
+      AUC (Ab Urbe condita) is a command-line Roman calendar tool. Currently it shows the specified date in the format of the Ancient Romans.
+    '';
+    license = licenses.mit;
+    maintainers = [ maintainers.kmein ];
+    platforms = platforms.all;
+  };
+}