Added a "Contracts" pass, after inlining, taking care of the
contracts of the nodes called in the body of a node. This pass
"inlines" the code and assume/guarantee parts of these subcontracts.
The "Sigali" pass both generates the sigali ("z3z") code and add the call to
the controller (which is a node generated further by the sigali tool).
Therefore this pass has been included into the mls compiler, and removed
from the targets (a "z3z" dummy target has been kept for backward compatibility
reasons).
Created two new files:
- utilities/global/compiler_options.ml: contains
the options that can be set using the cli
- utilities/global/errors.ml: contains global
errors definition
Misc now only contains helper functions that have
nothing to do with the ast or the compiler.
