ocamlPackages.janeStreet package set: init at 0.9.0

This contains a collection of Jane Street packages at version 0.9.0.
Packages not already present in ocamlPackages are also made available
without the janeStreet prefix.

pkgs/development/ocaml-modules/janestreet/janePackage.nix

@@ -0,0 +1,28 @@
+{ stdenv, fetchFromGitHub, ocaml, jbuilder, findlib }:
+
+{ name, version ? "0.9.0", buildInputs ? [], hash, meta, ...}@args:
+
+if !stdenv.lib.versionAtLeast ocaml.version "4.03"
+then throw "${name}-${version} is not available for OCaml ${ocaml.version}" else
+
+stdenv.mkDerivation (args // {
+  name = "ocaml${ocaml.version}-${name}-${version}";
+  inherit version;
+
+  src = fetchFromGitHub {
+    owner = "janestreet";
+    repo = name;
+    rev = "v${version}";
+    sha256 = hash;
+  };
+
+  buildInputs = [ ocaml jbuilder findlib ] ++ buildInputs;
+
+  inherit (jbuilder) installPhase;
+
+  meta = {
+    license = stdenv.lib.licenses.asl20;
+    inherit (ocaml.meta) platforms;
+    homepage = "https://github.com/janestreet/${name}";
+  } // meta;
+})