return nil
	}
	return fmt.Errorf("Site replication error(s): \n%s", strings.Join(msgs, "\n"))
}

func (c *SiteReplicationSys) newConcErr(errMap map[string]error, actionName string) error {
	return concErr{
		errMap:     errMap,
		summaryErr: c.toErrorFromErrMap(errMap, actionName),
	}
}

// concDo calls actions concurrently. selfActionFn is run for the current