Reindex section variables for typeclass resolution if their type changed.
Fixes bug #3331.
When discharging polymorphic definitions, we must take into account all
polymorphic variables of the section as they might incur universe constraints that
were used to typecheck the body of the definition, even if the variable
itself was not used. For "Monomorphic" variables, their constraints are already
always pushed to the global context. This fixes bug # 3330.
- Add an option to refresh only algebraic universes, for e_type_of. The goal
there is not the same as in Evd.define.
- Fixed bugs #3330 and #3331.
Less ocaml warnings.
Fixing #3390 (mismatch simple_tactic/tactic0 leading to segfault).
Fixing grammar in doc of Opaque as proposed by Jason (#3389).