[wg-camlp4] getting bitstring to work with Core

[Stephen Weeks]

> It's the build system integration that fills me with dread (figuring
> out the ocamlfind META runes, how to plumb this through to ocamlbuild,
> OASIS and OMake, and activate it only for files that use Core).

I see.  Waiting for namespaces might be the way to go then.

One way that might simplify the build-system nightmare a bit would be
to always have the Caml module in scope and to have bitstring always
generate references to it, whether or not one is compiling against
Core.