Notifications, Permissions and broadcast receivers (Exercise)

Another exercise as a supplementary for a lecture about Notifications, Permissions and broadcast receivers.

Presentation: https://docs.google.com/presentation/d/10xCnKDBKdPNuhw_R4qBaWpFDiZ4pVUVkAqRMyixL2-U
GitHub: https://github.com/Pulimet/PermisssionsBroadcastsNotificationsTutorial