adding deriving
Merge branch 'experimental/ocaml' into refs/top-bases/experimental/marc

* experimental/ocaml:
  adding deriving
Merge commit 'refs/top-bases/experimental/marc' into experimental/marc

* commit 'refs/top-bases/experimental/marc':
  adding deriving

Conflicts:
	pkgs/development/tools/ocaml/derivivg/default.nix