Log Message:
Updated lang/ocaml to 4.08.1.

4.08.1 is a bugfix release, fixing compilation failures in presence of the
-pack option, and dynlinking failures.

Highlights in 4.08.0 are:
* Binding operators (let*, let+, and*, etc). They can be used to
  streamline monadic code.
* open now applies to arbitrary module expression in structures and to
  applicative paths in signatures.
* A new notion of (user-defined) "alerts" generalizes the deprecated
  warning.
* New modules in the standard library: Fun, Bool, Int, Option, Result.
* A significant number of new functions in Float, including FMA support,
  and a new Float.Array submodule.
* Source highlighting for errors and warnings in batch mode.
* Many error messages were improved.
* Improved AFL instrumentation for objects and lazy values.