OBS: exit() -> sys.exit()

As pointed out in code review, sys.exit() should be used instead of
exit() from site.

https://docs.python.org/3/library/constants.html#exit says:
> The site module (which is imported automatically during startup,
> except if the -S command-line option is given) adds several
> constants to the built-in namespace. They are useful for the
> interactive interpreter shell and should not be used in programs.

Change-Id: Ia9d355e660afd1ad3c60064900d8be66e8e1d385
8 files changed