Fix program w.r.t. universes: the universe context of a definition changes
according to the successive refinements due to typechecking obligations.
This requires the Proof modules to return the generated universe substitution
when finishing a proof, and this information is passed in the closing hook.
The interface is not very clean, will certainly change in the future.
- Better treatment of polymorphic hints in auto: terms can be polymorphic now, we refresh their
context as well.
- Needs a little change in test-pattern that seems breaks multiary uses of destruct in NZDiv.v, l495.
FIX to do.
Fix [make_pattern_test] to keep the universe information around and still
allow tactics to take multiple patterns at once.
Merge branch 'univpoly' of /Users/mat/research/coq/git into trunk