Automatic code documentation

[tsani]

I try to write as much code documentation as I can. It would be great if we could integrate OCamldoc into the mix so that we can generate HTML documentation for the code. This would greatly help newcomers to the project so they can more easily locate files. For example, a newcomer may want to compose two msubs, but they don't know to look for Whnf.mcomp. We can write a comment on the msub type itself that links to Whnf.mcomp to facilitate this. In fact, perhaps all helper functions for working with msubs should be linked from the type definition of msub.

This would also help me since (I believe) merlin supports displaying documentation directly in Emacs, and there are a handful of functions whose argument orders can be mixed up (multiple arguments of the same type in a row).