update
Merge branch 'master' of https://github.com/Internship-AURIS/Project-AURIS

Conflicts:
	core/src/com/aau/auris/game/AURISGame.java
	core/src/com/aau/auris/game/items/BallSkin.java
	core/src/com/aau/auris/game/screens/ShopScreen.java
	desktop/userdata.json
Merge branch 'master' of https://github.com/Internship-AURIS/Project-AURIS
bugfixes, implemented Achievement, Level and Skin unlock