first version working with stateless contracts

src/backends/Ada/ada_backend.ml

src/backends/C/c_backend_common.ml

src/backends/C/c_backend_common.mli

src/backends/C/c_backend_header.ml

src/backends/C/c_backend_spec.ml

src/backends/C/c_backend_src.ml

src/backends/C/c_backend_src.mli

src/backends/EMF/EMF_backend.ml

src/clocks.ml

src/compiler_common.ml

src/corelang.ml

src/corelang.mli

src/lustre_types.ml

src/lustre_types.mli

src/machine_code.ml

src/machine_code_common.ml

src/machine_code_types.mli

src/normalization.ml

src/normalization.mli

src/optimize_machine.ml