use execpy if it is available
use execpy if it is available

The /execpy command allows us to run Python scripts without having to
hardcode the path to python.exe or pythonw.exe thus making it more
rebust. Obviously it comes with backwards compatibility and only works
when upgrading the Cuckoo Agent to the latest version.

cuckoobox/cuckoo,cuckoobox/cuckoo,cuckoobox/cuckoo,cuckoobox/cuckoo,cuckoobox/cuckoo