notify impersonated user with a notification and an email

[cagdasbas]

Attempt to solve #80
Notifier and mailer are mostly from quota_warning. A dirty hack but I'm willing to clean up with your feedback.

[nickvergessen]

I think a notification is enough for now.
We want to work a bit on the notifications soon, to allow receiving them as emails. So that would be doubled.

Otherwise I'm fine with the approach

[cagdasbas]

I think a notification is enough for now.

My thought was the same at first. But as soon as the admin user impersonates another, he/she can delete the notification. The user will only see it if already logged in at the moment. That's why I decided to add email notification.

How about deleting the email and adding an event to the activities of the user?

[nickvergessen]

But as soon as the admin user impersonates another, he/she can delete the notification.

Let me fix that instead.

[cagdasbas]

But as soon as the admin user impersonates another, he/she can delete the notification.

Let me fix that instead.

Sure. I'm removing the email then?

[nickvergessen]

Sure. I'm removing the email then?

Yeah, sorry for the huge delay

[nickvergessen]

Patch for notifications is at nextcloud/notifications#550

[blizzz]

• would be good to have the test related changes in a different PR
• translations do not go in via github, but transifex