Delete book from repository
Merge branch 'master' into feature/WB-106

Conflicts:
	worblehat-domain/src/main/java/de/codecentric/psd/worblehat/domain/BookRepository.java
	worblehat-domain/src/main/java/de/codecentric/psd/worblehat/domain/NaiveBookRepository.java
Merge branch 'master' of https://github.com/scrum-for-developers/2014-08-team-ham