//Init an allocated NotifyStorage
func (ns *NotifyStorage) Init(daemon_freq int64) {
	logger.Println("init notify storage")
	ns.MapStorage.Init()
	ns.bg = make(chan expiry.Entry, 100)
	ns.heap = expiry.NewHeap(100)
	go ns.ExpiringDaemon(daemon_freq)
}
//Init an allocated HeapExpiringStorage
func (hs *HeapExpiringStorage) Init(collect_frequency int64) {
	logger.Println("init heap notify storage")
	hs.heap = expiry.NewHeap(100) //TODO, size as config parameter
	go hs.CollectTicker(collect_frequency)
	go hs.ProcessUpdates()
}