implement notification service and API
|Reported by:||wkornewald||Owned by:||pulkomandy|
We need a very simple API for creating notifications and a way for users to subscribe to notifications, so when an event occurs a pop-up can be shown, for example. The details still need to be discussed and maybe a short specification from the end-user point of view needs to be written.
This is probably an R1.1 task, though.