When incorrect commandline arguments are passed, the output is directed
to stdout instead of stderr.

This change set fixes this, and also makes sub-commands
that return error to terminate with error code of 1
instead of 0.

Change-Id: I3e9c2172d91b25829e5b9c81aa3e812a205c9cf5
Signed-off-by: yacovm <yacovm@il.ibm.com>