Remove a lot of warnings (considered as errors by dune).

In other words, consider ">" and co as overloaded operators, not polymorphic ones.

The rationale is to avoid local vars blow-up on some
examples. Indeed, the generated oracle blows-up (e.g., on left.lus)
if we execute it via v4, whereas via v6 it works fine.

This change triggers a couple of bugs that ware easy to fix
(confusion between div and slash) that I've fixed along the way.
For the others, I'll see later.

Overall it's a progress albeit
  #fail: 80 -> 83

indeed:
  #unresolved: 20 -> 12
  #passes		878 -> 883
  time: 335 -> 228

1) At the Lic level, there's no reason to distinguish betwenn node
calls, and predef node calls. Indeed it makes things simpler and more
homogeneous afterwards.

2) int strings are only converted when necessary (constant evaluation).

3) const are handled directly under Lic.by_pos_op instead of being under
   PREDEF_CALL, which make things easier and more logical.

nb: les tests ne passent toujours bien sur.

* Partie lus -> AST

predef.ml -> srcPredef.ml
syntaxTreeCore.ml -> astCore.ml
syntaxTree.ml     -> astV6.ml
syntaxTreeDump.mli-> astV6Dump.mli

* Partie Ast -> Ast

solveIdent.mli -> astRecognizePredef.mli
syntaxTab.mli -> astTab.mli
symbolTab.mli -> astTabSymbol.mli

* Partie  AST -> lic (static evaluation)

eff.ml  -> lic.ml
getEff.mli -> ast2lic.mli
lazyCompiler.mli -> licTab.mli
builtIn.ml -> licMetaOp.ml
predefEval*.ml -> licEval*.ml
name.mli -> licName.mli

* Partie Lic -> Lic

uniqueOutput.mli      -> l2lCheckOutputs.mli
structArrayExpand.mli -> l2lExpandArrays.mli
nodesExpand.mli       -> l2lExpandNodes.mli
doNoPoly.ml           -> l2lRmPoly.ml
doAliasTypes.ml       -> l2lAliasType.ml
doSplit.ml            -> l2lSplit.ml

- plus de macros prefefinies (e.g. FILL, BOOLRED etc...)
  (remplacé par la notion de BuiltIn)
- split.ml adapté et remanié pour rentrer dans le moule
  source to source (voir DoSplit)

et donc ne marchent plus !

iterated, was still printed using the prefix/long name method (e.g.,
"Lustre__not(a)"  instead   of  "not  a").   Moreover,  equality  was
inconsistently represented as "eq" and "equal". I choose the former.

In  short, the  rationale for  this change,  is that  it is  having a
recursive node_exp is
- useless,
- too complicated,
- wrong w.r.t. nesting iterator calls

In long:

- It is useless because, at the  Eff level, a node cannot call itself
  via one  of its  static arg (which  was where the  recursivity came
  from).

- and indeed, it  is much simpler to consider that  a static arg node
  can only be ident.long that identifies a node alias.

  This  means of  course, that  nested iterators  have  been unnested
  before,   inventing  alias   node  names   along  the   way...  And
  polymorphism makes thing difficult once again.

- But the  *big* problem  with a recursive  node_exp is that  it make
  things very  complicated to (lic)dump nested  iterator call because
  of polymorphism!   Actually, it  even makes thing  complicated when
  the iterators were themselves not nested in the source code !

  Some ugly  things were done in  LicDump to unnest  those calls when
  printing node_exp.   But this uglyness  have a price:  tricky code,
  and bugs! Indeed, nested iterators calls were wong for example when
  using  the --inline-iterator  mode (but  i would  not  be surprised
  that is wrong in other cases...).

Hence,  LicDump  is  simpler,  but  of course  LazyCompiler  is  more
complicated.  But  this  is  reasonable:  a  pretty-printer  is  not
supposed to be complicated.

to avoid priority errors.

iterators (e.g.,  "Lustre::plus" instead of "Lustre::+")  in order to
make the life of lic3loc easier.

to avoid priority errors.

and PredefEvalClock.

SolveIdent.recognize_predef_op  that  replaces  node call  by  Predef
constructor  when   necessary,  via  a  complete   traversal  of  the
SyntaxTree (instead  of doing it  in the parser). The  rationales for
this change are that:

- it is quite tedious to do it in parser as multiple locations are involved
- I did missed some locations
- It makes the parser more focused on parsing issues
- that traversal  is a first step  do deal with  idref solving (hence
 the name of the new module that contains that function

Note that lsrc/test/should_work/fab_test/lecteur.lus was using
"plus" as a variable ident, which raised an error, which

performed. The resulting code is both more compact, and more general.

It is more  general, since that predef operators  are now represented
by  node_exp_eff, exactly as  user nodes.   Hence, all  the functions
that were  operating on  user nodes via  node_exp_eff (such  as, node
aliasing) works for free on predef op!

In order to be able  to perform that generalisation, it was necessary
to  extend sligthly  the data  structure used  to represent  the node
profile in CompiledData.node_exp_eff with information indicating if a
variable is polymorphic or overloaded.

Not that, currently, polymorphic  or overloaded variables can only be
introduced by predef  operators. But I think it would  be easy to add
those notions for normal user nodes after this change.

New non-reg files boolred now compiles. Those involving
- boolred
- alias on predef.op

(support for fill, red, etc. is coming soon).

In order to add support  for iterators, I have extended the by_pos_op
(and the by_pos_op_eff) data type with a list of static arguments. In
other words, iterators are handled as a particular case of predefined
operators.

tests.

Also, Add the possibility to have several lustre files in the
command-line arguments.

remove the power operator.

Define a lustre.lus that contains a packaged version of Lustre
predefined operators. It will be in the standard lustre library,
and should be accessible directly (path).

For non-regression tests, do not use Lazycompiler.test function
anymore and just use  LazyCompiler.node_check instead.

put in the new file compiledDataDump.ml all the stuff
related to string convertions of CompiledData items.

and anonymous structures. I've even found some type errors in the non-reg files!

operators. Predef contains the abstract syntax of those operators (taken
for SyntaxTreeCore.by_pos_op), and PredefSemantics contains:

 - const_eval: that says how to statically evaluate constants
 - type_eval: that provides the type profile of predef operators
 - clock_eval: that provides the clock profile of predef operators

The code in EvalConst that dealt with predef const evaluation is now in
Predef.const_eval