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

Indeed the API of Format.formatter_out_functions changed in 4.06.0

To turn around this problem, I've used pp_get_formatter_out_functions
and extend it result

And it is now done only by Lic2soc (L2lCheckLoops is not used anymore)

Also, during this change, I was bitten again by the « "__" versus "::" in ident
names » problem again.

The core of this problem is due to the fact that I use LicDump both for
(1) dealing with internal ident names
(2) generating lustre files

Because of (2), ident names may depend on the ec or the v4 option. hence, internal
names were sometimes translated with "__" instead of "::".

To (try to) fix that, I've added a boolean flag to all "to_string" functions that
states whether the function is used for internal purposes, or for generating lustre
files.

It was quite a boring change, that triggered other problems, that I've fixed
in this (too long) commit :
 - -esa should force -en, otherwise bad things happen (-esa is used for -ec anyway)
 - in -esa mode, #/nor inputs tuples of bool, not arrays
 - fix the list of predi op that returns a type different that its arg (SocPredef)

  More precisely, a node that has memory ougth to be declared using
  "node", and using "function" otherwise.

  Moreover, a node that performs side-effects (i.e., if it calls an
  extern node that performs side effects) ougth to be declared as
  "unsafe".

  Safe/unsafe mismatches raise an error.

  Memory mismatches raise an error in one way (a "function" that uses
  memory), and a warning in the other way (a "node" that uses no
  memory).

Also fix some errors done when transmitting the unsafe flag (well, it's
the first time I use it!).

Actually it does not fix any test, but I feel it is a (slight)
progress, so I commit it... Well, to be fair, one objective progress
is that I can now compile the test suite with the -np option.

In order to do that, I've generalised the type of merge : now the clock
argument can be any expression. Some assert false still prevent its use,
but it should be easy to get rid of them (I'll do that latter).

nb : programs do run, but I did not check that they run correctly...

Also fix a regression introduced in the previous change where
incorrect ec code was generated for diese.

Pascal prepared « the field » for that change.

Also, force the merge to operate over an ident rather than on any val_exp.

nb : do not work for lv4/ec mode

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 !

by position). Rename ExpandPack into InstanciateModel.

change the parser and accept only clock expressions after a when.

A clock is now made of 2 idents: one for the clock constructor, and
one for the clock variable.

equations is not done at all yet). Also, print the clock decorations
(when clk) in the generated file.

work yet though (returns the wrong type).

Also add the struct printer, and fix a bug in the static argument printing.

Also, node aliased to other nodes were handled poorly: I was replacing
in the syntax tree the node by its alias. Now, I really define
the alias node using the aliases one.

For instance,

    node toto(x:t) returns (y:t);
    let
      ...
     tel
     node titi = toto;
     node tutu(...) returns(...);
     let
        ...
	z = titi(a);
     tel

was compiled into

    node toto(x:t) returns (y:t);
    let
      ...
     tel

     node tutu(...) returns(...);
     let
        ...
	z = toto(a);
     tel

Now, I generate

     node toto(x:t) returns (y:t);
     let
       ...
     tel
     node titi(i1:t) returns (o1:t);
     let
       o1 =toto(i1);
     tel
     node tutu(...) returns(...);
     let
        ...
	z = titi(a);
     tel

which is equivalent, but closer to the original program.

(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.

	type 'a hereflagged =
	  Here of 'a
	| NotHere of Ident.long
into
	type 'a elt =
	  Local of 'a
	| Imported of Ident.long * static_arg list

i.e., i am basically doing two things:
 - fix poor naming
 - adding static arg to nodes

indeed, when compiling an equation that involves nodes defined
in another package, I need to check that the static args and the
static params match. Therefore I need to have the static params !
Therefore I add them (I will use them in the next commit).

Moreover, in SyntaxTreeCore.node_info, the static_params list was
an option type, which is a bit weird (empty lists are enough to
represent node with no static params).

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).

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

used in order to make it homogoneous with what is done in SyntaxTreeCore.ml

This commit is related to the previous one actually.

Also remove all this story of node_half_eff that is not
used (yet), and that may not be useful (we'll see later).

Also continue to fix the representation of SyntaxTrreCore.node_info :
 -> remove the node alias
 -> put the corresponding infomation in node_body field
 -> rename node_body field into node_def
 -> associate to node_def (instead of a body option) a new union
type made of Abstract, Extern, Alias of ..., Body of ...

This allows us to
 - remove an "assert false" to deal with node with body and alias
(this new presentation makes it impossible)
 - Deal with Abstract node properly

change is
	- make the parser simpler
	- make the compilation simpler
	- make everything simpler actually...
	- accepts more correct programs.
	- etc.

Indeed, before, we had specific syntax nodes for
	- extern nodes
	- aliased nodes
	- abstract nodes
	- normal nodes
which leads to duplicate code everywhere. Now, we have a more generic
representation.

The nice thing is that the parser is much simpler, and a lot of
duplicated code is avoided (for example, extern and abstract nodes do
now share the same code).

The bad thing is that we have more "assert false" lying everywere due
to this «too rich» representation, in order to deal with cases
that can never happen. For exemple, we have to do something with
nodes that have  both an alias and a body. This cannot happen of
course, so we issue an "assert false", which is a little bit painful,
as it have been rejected by the parser anyway.

Moreover, for some reason, external node params could not be clocked,
and cannot have static params. Maybe it is not possible to compile
such nodes (I don't know yet), but we should not raise a syntax error IMHO.

Somehow, what was done was very similar to ask the parser to perform type
checking.

EvalNode.f

rename back predef_node into by_pos_op.

i.e.,
	a = operator +(1,3);
or
	a = map<<operator +>>(l);

This is to simplify the syntax tree. We migth undo this change in the
future, or perform the same thing differently.