Delete Dummies
Merge https://github.com/bertrandjackermann/Bibliothekenverwaltung into abstractView
some changes at StockView etc
Merge https://github.com/bertrandjackermann/Bibliothekenverwaltung into abstractView
Reservierungslogik
StockLogic
stockView and Mapper
Merge https://github.com/bertrandjackermann/Bibliothekenverwaltung into abstractView