// upon Wait() errors are returned collected from all tasks, optionally allows for X workers
// only "per" parallel task.
func WithNPeersThrottled(nerrs, wks int) *NotificationGroup {
	if nerrs <= 0 {
		nerrs = 1
	}
	if wks > nerrs {
		wks = nerrs
	}
	wk, _ := workers.New(wks)
	return &NotificationGroup{errs: make([]NotificationPeerErr, nerrs), workers: wk, retryCount: 3}
}