fix: some issues in the lustre backend wrt =current=

(and a --2smv one that is not finish)

nb: still does not work for nested iterators

(It would have avoided issue #8)

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

update the Arduino demo

Remove unused files along the way (myGenlex.ml/mli)

nb: the 2 tests that now pass pass for other reasons (because of a change in
rdbg 1.108)

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)

Also, -eeb is now the default when using -ec.

To do that, I have created a new dedicated module L2lExpandEnum, that
actually also deals with -eei (which was probably wrong, even if I
have not counter-exemple).

Use 1-hot encoding instead of log-encoding

I've fixed a bug in L2lExpandArrays that occurs on equation such as
  some_bool = (some_array1 = some_array2);

Also, I've rewritten Lv6Compile for more readability

Remove duplicated code when using SocMap.find and co

Also, use rdbg instead of lurettetop to run the test.

Reference Manual enhancements.

so that w7/lesar can help otawa/ilp to prune path in the binary.

nb : not working on the convertible example:
 - sometimes the module name still appear in the ident (enums)
 - clocks are not well supported by Lesar actually. More thinking is necessary.