Z3 apparently supports them, but any attempt to use thme makes Z3 segfault

Module bitvec

thanks to Johannes Kanig

Submitted by Johannes Kanig

this is useful to declare on-the-fly a new sort which replaces
a complex type. Otherwise, the printer has to traverse any term
twice: first, to detect complex types, second, to print the term.

also, avoid the "encoding_sort" transformation, if it can be done
directly in the printer.

On the same example as in the previous commits, this gives 5x
acceleration together with some memory usage reduction.

(inspired from patches provided by Piotr Trojanek)

we really, really should implement blacklists in drivers

	Just a proposition for a more controllable why3replayer

+ create AUTHORS file
+ fix the linking exception in LICENSE
+ update the "About" in IDE
+ remove the trailing whitespace
+ inflate my scores at Ohloh

 (metas, debug flags, transformations, formats) except for label.

This description is used in --list-*. The description can use any of
the formatting markup of Format "@ " "@[",...

Transformations can also specify from which metas and labels they
depend, and add informations about how they are interpreted.

TODO:
  - complete and correct the documentation
  - when a transformation use Trans.on_meta, it should be possible to
    add an interpretation of the metas in the documentation.
  - recover a summary version of --list-* ?
  - be able to export in latex?

side-effect: function syntax in driver now accepts %v0, %v1, etc.
for type variable instantiations (order is given by variable name)

- put abstract types and aliases in Dtype of tysymbol
- put (recursive) algebraic types in Ddata of (ts,constr list) list
- put abstract function/predicate symbols in Dparam of lsymbol
- put defined logic symbols in Dlogic of (ls,ls_definition) list

also, remove all customization from the Z3 3.x section in prover detection.
I find it morally wrong to chase magic options of a closed-source program.
We should add an option for a prover only when we have clear understanding
of what it does and good reasons to believe that it is useful in our case.

but not use it by default, because of bad caching of smt_encoding
transformations. Because of this, new function symbols appear again
and again, and since we don't forget function symbols in trans-based
printers, we obtain names like at234.

also, introduce in Printer the p-printing transformations

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.