 
     private let userNotificationCenter: NSUserNotificationCenter
     private var notifications = [Notification]()
+    private var timer: Timer?
 
     private init(userNotificationCenter: NSUserNotificationCenter = NSUserNotificationCenter.defaultUserNotificationCenter()) {
         self.userNotificationCenter = userNotificationCenter

        let userNotification = NSUserNotificationBuilder.build(notification)
        notifications.append(notification)
        userNotificationCenter.deliverNotification(userNotification)
    }
}


extension NotificationCenter {

    func clearAllNotifications() {
        timer = nil
        userNotificationCenter.removeAllDeliveredNotifications()
        notifications.removeAll()
    }
