stacking notifications in android

lib/pushnotificationsservice.js

@@ -125,6 +125,7 @@ PushNotificationsService.prototype._sendPushNotifications = function(notificatio
                 "title": content.plain.subject,
                 "message": content.plain.body,
                 "walletId": sjcl.hash.sha256.hash(notification.walletId),
+                "notId": Math.floor(Math.random()*100000)+1
               }
             };