android 13 compatibility (bitfireAT/davx5#155)

* check for notify permission before notifying

* [WIP] add notification permission request

* Revert "check for notify permission before notifying"

This reverts commit ed8e046d73163bef5684622bd877f08b9ee781c6.

* add notification permission request

* [WIP] add notifications disabled card in accounts view

* add notifications disabled card in accounts view

* reorder permissions

* use dp instead of mm for image max height in permissions view

* stop using array to bundle notification permissions

* Use new permissions contract for PermissionsFragment

Co-authored-by: Ricki Hirner <hirner@bitfire.at>