Arguments for the Multi health monitor plugin.

def add_arguments(cls, parser, sys_arg_list=None):
        """
        Arguments for the Multi health monitor plugin.

        """
        parser.add_argument('--multi_plugins',
                            dest='multi_plugins', required=True,
                            help="Column seperated list of health monitor "
                                 "plugins (only for 'multi' health monitor "
                                 "plugin)")

        arglist = ["multi_plugins"]

        # Read the list of the specified sub-plugins ahead of time, so we can
        # get their classes and add their parameters.
        sub_plugin_names_str = \
                utils.param_extract(sys_arg_list, None, "--multi_plugins")
        sub_plugin_classes = \
                cls.load_sub_plugins_from_str(sub_plugin_names_str).values()

        # Store the list of the sub-plugins in the class, so we can iterate
        # over those during parameter evaluation later on.
        cls.multi_plugin_classes = sub_plugin_classes

        # Now also add the parameters for the sub-plugins
        for pc in sub_plugin_classes:
            arglist.extend(pc.add_arguments(parser, sys_arg_list))

        return arglist