added import ArrayList in InventoryItemRepository
Merge branch 'master' into nadja
added RequestMappings for destructLivingSpace and repairLivingSpace + thymleaf in platzverwaltung.html + chenged call of repairLivingSpace in BalanceController + added OneToMany annotation for Repairs in LivingSpace
only minor conflicts in BalanceController - there's one little error that I will correct right after this
changed the type of the local variable 'repairs' in calcRepairBalance() in BalanceController from ArrayList to List