Fix il/li tag

The smoke detector try to detect when a goal is proved
because the context is self contradicting.

The way it is configured in session is not very pretty.

(standalone executable why3realize)

also, introduce in Printer the p-printing transformations

meta "instantiate : auto" on as many terms as possible.

The transformation is rather naive, since it doesn't look for term
candidates under quantifiers, if-then-else, let-in, and so on. So it can
only appear late in the transformation pipe.

It is only enabled for Gappa and its target axioms are the ones that state
that any floating-point value is bounded. It was the last transformation
from Why2 still missing in Why3.

Thanks to this transformation, Gappa is now able to prove all the safety
obligations from the following code, including the ones about division and
downcast, which is definitely frightening.

/*@ assigns \nothing;
  @ ensures \result == \abs(x);
  @*/
extern double fabs(double x);

/*@ requires \valid(AB_Ptr) && \valid(CD_Ptr);
  @ assigns *AB_Ptr, *CD_Ptr;
  @ ensures \abs(*AB_Ptr) <= 6.111111e-2;
  @ ensures \abs(*CD_Ptr) <= 6.111111e-2;
  @ */
void limitValue(float *AB_Ptr, float *CD_Ptr)
{
   double Fabs_AB, Fabs_CD;
   double max;

   Fabs_AB = fabs (*AB_Ptr);
   Fabs_CD = fabs (*CD_Ptr);

   max = Fabs_AB;
   if (Fabs_CD > Fabs_AB)  max = Fabs_CD;

   if ( max > 6.111111e-2)
   {
      *AB_Ptr = (float) (((*AB_Ptr) * 6.111111e-2) / max);
      *CD_Ptr = (float) (((*CD_Ptr) * 6.111111e-2) / max);
   }
}

Prover capabilities are now represented by a record enumerating each case and which syntax to use then.
This fixes output of nondecimal integers to provers (bug #12981).

TODO: check whether some provers support more than just decimal representations.

This reverts commit 99554a05.

add the way of replaying examples in the doc

new syntax 'L: to introduce a mark
new syntax at t 'L in logical expressions

Warning since 7efae3f8 yices doesn't
work with real since in assoc_mul_div a variable is the denominator.
Yices refuse that.

instead of $libdir/plugins. We have no other binary components.

in particular, there is no more need to define intermediate
sorts or to close the set of protected types wrt subtyping

You must run ./config.status after this commit