Ensure ssh_args in config file is honored

Because the default value is defined for --options parameter, the config file value was always overwritten

Only use --options if config file option is not defined and --options is not the default value

lib/App/ClusterSSH/Getopt.pm

@@ -307,6 +307,8 @@ sub getopts {
 #                    ? $self->{command_options}->{$acc}->{default}
 #                    : undef;
             };
+            my $accessor_default=$accessor.'_default';
+            *$accessor_default = sub { return $default; };
         }
     }