cleanup Makefiles for ocaml use newer findlib features

[flixr]

When trying to add netclient I was annoyed by the all the config needed to link the ocaml code and found this:
http://stuff.mit.edu/afs/sipb/project/ocaml/src/other/netclient-0.3/README

IF YOU HAVE FINDLIB-0.2 OR NEWER:

This version of "findlib" is much more convenient. It comes with a new
frontend for "ocamlc" that is intelligent enought to find out most of
the compiler/linker options itself.
Link with
ocamlfind ocamlc -custom -o output -package netclient -linkpkg

Also the includes, libs, etc.. needed for ocaml are repeated in a lot of makefiles. Should be cleaned up to use one common makefile for this and using new findlib would probably also help a lot.

It might make even sense to switch to CMake to find all the dependencies... but that is another issue for later...

[flixr]

sw/tools/Makefile already uses ocamfind with the package option to find/include the libs. Not sure if that can be use for ocamlmklib as well...