[typing] improve typing of operators by preventing propagation of the context to the operands. This way, it prevents to introduce useless type coercions. Indeed, the typing context is only useful to limit the number of generated casts when typing the _result_ of the operation.

[tests] Compare the generated code just after running Value. Use gcc_x86_64 as machdep for all these tests.
[tests] call testrun.sh in test_config in order to compile and run the generated code. This code is no more the one being compared with the oracle (see above item).

[quantif] updated according to AST changes: && is now left-associative

[E-ACSL] improve ACSL contracts of its libraries
[E-ACSL] no more unknow locations in translation of quantifications

[E-ACSL] fixed bug with global declarations involved in the memory model (btw fixed but #1392)
[E-ACSL] additional feedback messages