Added ocamlbuild system w/ scripted C file gen

- bv{8,16,32,64}.[ch] generated by myocamlbuild.ml.
- can link and build entire library. God I hope this scales.

- I had issues with bv* in the bitvector subdirectory, even with
  <bitvector>:include. I'm really not sure why things did not parse well.

- I've left the build files in the root directory. This may be annoying in the
  future having to add lib/ to everything, but I would like to keep the build
  files and the source files separate.