formatting

ast modifs and additional arrow_taint phase to retrieve which arrow "protects" / "taints" which variable

Contract resolution still need to be done as well as dealing with the machine code level and so on.

node_Table hashtbl is now only available through functions of the corelang.mli

- Renamed type declarations as lustre_types and machine_code_types

[main] node locals are now sorted according to their dependencies wrt clocks. The produced lustre node with types shall now be compilable

const that are not dimension types should not be used to evaluate dimension expression. This happened with const variables denoting real values.