unit tests
bugfixes
Merge branch 'datastructure' of github.com:Roconda/SudokuComponents into datastructure

Conflicts:
	src/main/java/nl/avans/SudokuDatastructure/BoardDS.java
	src/main/java/nl/avans/SudokuDatastructure/DsArray.java
	src/main/java/nl/avans/SudokuDatastructure/Field.java
Import lib package