add unsafe_map functions + rewrite abstraction/instantiation
add unsafe_map functions + rewrite abstraction/instantiation


jpdeplaix/why3,ssaavedra/why3,douglas-larocca/why3,douglas-larocca/why3,jpdeplaix/why3,douglas-larocca/why3,jpdeplaix/why3,ssaavedra/why3,ssaavedra/why3