Adds methods in the UserInterface as well as a test case in main
1
Adds save- and load books files
testar för att fixa no-fast-forward
Merge branch 'master' of https://github.com/tonysegeras/Lab3Del2.git

Conflicts:
	Lab3Del2/src/TonyJocke_Lab3Del2/Book.java
Revert "Merge branch 'master' of https://github.com/tonysegeras/Lab3Del2.git"

This reverts commit 5c09053042b6eea8ab09d4209b9ba9342cf60108, reversing
changes made to c3094b5dd96167c290ccf2f535d60bd1ba258d33.
Förstör lite grejjer