WIP
Use ocamldep to infer dependencies in a directory

Seems that the API is not easy enough to use, with few convenient functions and goodies to help the user:
- use ocamldep instead of specifying the dependencies manually
- The C stub generation is compiling (need to test it now)
- The test API is a bit more complete (can now run sequence of commands)

The library bootstraps again. Really need to test the C stubs generation and then cut a release.