Not comprehensive yet. Only planning to do setools pkg (not policyrep),
with the exception being the SELinuxPolicy class in policyrep.
Avoids performance-critical paths. Use only info and debug so in normal
cases the user only sees messages if they ask for it (e.g. -v).
Catch all exceptions in the main bulk of the CLI code. We can't do anything
if there is an exception, so either print the error message from the
exception, or print the traceback if debug is enabled.
