[et-mgmt-tools] [PATCH] Fix traceback on commands run with -h

[Michael DeHaan]

>
> It is only legal in python >= 2.5, so you'll need to fix that if you
> support 2.4 or earlier for cobbler
>
> Dan.
>   

Yep, I settled on just:

except SystemExit:
pass

just because on SystemExit optparse has already printed what it wants to 
print, and we don't use SystemExit elsewhere.

This has been your daily python lesson on et-mgmt-tools at redhat.com :)

--Michael