Refactoring: factor out fix-match typing.

[ref #17094]
Refactoring: factor out operators axiomatization.

[close #17094]
Doc: elim*, exists*, and typo in exfalso.
Script for creating bbox (linux 32/64)
Doc: fix some typos and improve layout.
Print types in 'print glob A' in the right order.
Add an Hilbert-epsilon operator.

Syntax is `choice opname with lmname` where `lmname` is the name of a
lemma of the form: `forall (x1 : t1) ... (xn : tn), exists y, P y`.

The resulting operator is s.t.

`forall (x1 : t1) ... (xn : tn), P (opname x1 ... xn)`

It doesn't have any computational contents.
Typos (comments in stdlib)
PG: update keywords
New library on quotient.

Incomplete, missing the construction of a quotient from a equivalence
relation.
Doc: General but quick pass, marking things to do and fixing typos.
Merge branch '1.0' of git://ci.easycrypt.info/easycrypt into 1.0