Post Notification when Movie from Watchlist is released

[fbernutz]

Implement with scheduled local notifications.

1. When a user adds a not yet released movie to the watchlist:
   Schedule one local notification for 10h on the release date "{Title of movie} is released today!"
2. When a user removes the movie from the watchlist:
   Delete the local notification again

For more information about how this should work:
https://developer.apple.com/documentation/usernotifications/scheduling_a_notification_locally_from_your_app

[fbernutz]

Maybe this will be helpful implementing this feature: https://github.com/nicephoton/ScheduledNotificationsViewController