Add indicator for changed elements

[d-Rickyy-b]

This is very nice especially when many classes are cancelled and a new one gets cancelled aswell. That way you can see the specific class right away.

https://github.com/matrixxun/MaterialBadgeTextView

https://stackoverflow.com/questions/43194243/notification-badge-on-action-item-android/43195893

[d-Rickyy-b]

The app is no longer of any use, since the actual time table is behind a login now.