added lib/ints.py with renamings of max()->set_*min*(), min()->set_*max*() for easier understandability of the set-ceiling/set-floor use cases of min()/max()
added lib/ints.py with renamings of max()->set_*min*(), min()->set_*max*() for easier understandability of the set-ceiling/set-floor use cases of min()/max()