Properly deny anonymous users access to Private Storage

Description

When users that are logged in anonymously try to use private storage, an internal-server-error is returned:

Anonymous users are not allowed to have PEPServices in Openfire, which is why this won't work.

Instead of the internal-server-error, a feature-not-available should be thrown. The feature should not be advertised through disco#info either, for these users.

Environment

None
Fixed

Assignee

Guus der Kinderen

Reporter

Guus der Kinderen