Safeguard against missing configuration in JSON.
Musik

- unnütze Dateien deleted
- Effekte leiser
- loop-Zeiten angepasst
Merge branch 'lessMusic' of https://github.com/mayermi/turtle into mayermi-lessMusic

Conflicts:
	js/models/player.js
	turtle.js
Set type and layer in level configuration. Do not create clouds under
water.
Remove files we no longer need.
Rename audio-files.
Rename audio files again, because casing.