make argument parsing more verbose

This greatly enhances the --help output of the lab binary, as well as allows for long option names (i.e. ```--threshold 80```), and correctly parsing boolean flags

It does come with the side effect that to turn off global leak detection, instead of providing ```-g 0``` as before, you would provide ```-g0``` (with no space), ```--no-g``` or ```--no-global-leaks```