Can we return status codes to the command line from the enforcer-ng command utility?

In 1.4 the 'ods-ksmutil' command utility return 0 or 1 as a return code, depending on the success or failure of the command. 2.0 currently doesn't do this so this issue opened to review how/if we can address this.

Note also the request from Rick: https://issues.opendnssec.org/browse/OPENDNSSEC-404

We should at least come up with a consistent set of rules to apply to all commands as to how the return code should be set if we provide one.