* aclocal.m4: Add AC_CHECK_OCAML_MODULE to check for OCaml
modules directly (without ocamlfind being needed).
* configure.ac: Remove requirement for ocamlfind.
* config.guess, config.sub: Ship these files to guess host,
build and target.
* libvirt/Makefile.in, examples/Makefile.in: Change these
so they don't require ocamlfind, do the right thing on MinGW.
* Make.rules.in: Make.rules is now generated from this file.
File can use ocamlfind or direct ocaml commands as available.
* .hgignore: Ignore some generated files on Windows.