Refactor all notifications from extensions and UI toggling such that …

[thecalcc]

SDBELGA-818

• Registered notifications are displayed with value true even if a user doesn't have them saved in preferences
• Email notification group toggling works and does toggle all sub notifications no matter if they haven't been set before by the user, or if they have been
• Saving works in both cases
• Canceling works in both cases
• Desktop notifications aren't shown in the notifications sidebar if a user has toggled them off
• Email notifications aren't received if a user has toggled them off

[tomaskikutis]

does this unified notification notify both of marking and unmarking? Check with if API exposes this information and coordinate with Petr if not

[thecalcc]

Yes, works for marking and unmarking. Only difference between the two previously was the body message, handler was indeed the same one.

[tomaskikutis]

let's verify that unified notification works (mark/unmark) including enabling/disabling