Bug/bts1831 (argc / argv)

Implements 1831

 - fix indentation
 - follow the model of must_init, build_initializer
 - only generated code if generate is set,
 - generate code "on project".
 - rename mainargs.i -> mainargs.c

Bug/bts1836 (off by one in bittree)

Bug/bts1836 (off by one in bittree)

propagate change according to kernel changes about vlogic/vgenerated; but Misc.is_generated_varinfo is much less efficient than before

also change gcc_test.sh so that one can pass arguments to program
under test.

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

update code and oracles according to Frama-C changes, in particular interpretation of \valid in presence of const

resync master and stable/neon

Conflicts:
	label.ml
	pre_analysis.ml
	tests/e-acsl-runtime/oracle/bts1399.1.res.oracle
	tests/e-acsl-runtime/oracle/bts1399.res.oracle
	tests/e-acsl-runtime/oracle/call.1.res.oracle
	tests/e-acsl-runtime/oracle/localvar.1.res.oracle
	tests/e-acsl-runtime/oracle/ptr_init.1.res.oracle
	tests/e-acsl-runtime/oracle/valid.1.res.oracle
	tests/e-acsl-runtime/oracle/valid.res.oracle
	tests/e-acsl-runtime/oracle/valid_alias.1.res.oracle
	tests/e-acsl-runtime/oracle/valid_alias.res.oracle
	tests/e-acsl-runtime/oracle/vector.1.res.oracle
	tests/e-acsl-runtime/oracle/vector.res.oracle