e.g., by replacing "plus" by "iplus" or "rplus"

Hence now the following is accepted :
   res = map<<+,  N>>(x, a, b);

but still not

  a_or_b = map<<Lustre::if,  N>>(x, a, b);

For instance,
  node toto = map<<Lustre::if,  N>>(x, a, b);
is rejected.

The problem with this change is that we now also reject equations such as
   res = map<<+,  N>>(x, a, b);

which could be avoided. Probably L2lRmPoly does its job partially.

nb:  unexpected failures  120 -> 118

nb:  unexpected failures  115->120

nb:  unexpected failures 120 -> 115

nb:  unexpected failures 126 -> 120

nb:  unexpected failures 127 -> 125

I've sligthly modified the profile of gen_assign to explicitly ask for the
size of the data structure to be copied.

nb:  unexpected failures 131 -> 127

nb:  unexpected failures 133-> 131

nb:  unexpected failures 143->133

nb:  unexpected failures	144->143

nb:  unexpected failures	149->144

The arrow soc now has a memory used to hold if the first step has be triggered.

The first one in Soc2cIdent.type_to_short_string when enum and int were both
translated by "i" ; as a consequence, some different soc ctx get the same name.

The second one was due to the fact that car ident in gao switches were
printed incorrectly (missing "ctx->" or "node_no_mem_ctx.").

nb:  unexpected failures 162-> 149

nb:  unexpected failures 175-> 162

Also name step function consistent and uniquely

nb:  unexpected failures 187->175

nb:  unexpected failures 195->187

Also start to add support for the other iterators, but it does not work yet.

The idea is that
- when it is not in the memory, it is considered as true
- it is set to false after each step is executed

test: 203->198 failures

test: 238->203 failures

nb: 20 more tests passes.

Always use Soc2cPredef.gen_assign to generate var assignments.

Also, use affection for assigning structures.

nb: 21 more tests passes.

Also do not crash if the soc contains reference to extern types.

To do that, I've used the (un)expand_profile function defined in SocExec
(and put the in a new module with a more neutral name: SocVar).

expected passes		1116 -> 1121
unexpected failures	282 -> 277

of expected passes		1073 -> 1116
of unexpected failures	325 -> 282

Indeed, Soc with memory can be used several times; hence we mark the
set of visited soc while printing the soc typedef.

 of expected passes		1052 -> 1073
 of unexpected failures	346 -> 325

46 ok, 159 ko...

121 ok, 110 ko. Basically, ko programs contains arrays arrays and
structures.