On browser refresh, the bus sends the last notifications for the last
50secs. This is really annoying to deal with, especially in the chat
applicatiion. This commits ensure that duplicate notifications are
ignored. This is done by saving the id of the last notif in the local
storage.
Note: it is also necessary to clear the last message id in the local
storage to prevent problems when a developer resets his db, and will not
receive any notifications.
Géry Debongnie
1378dc130c