Merge pull request #128 from bkng/master

Fixed exception caused by empty Difficulty setting
Fleshed out UserInfoTest

Conflicts:
	InterviewAnnihilator/src/com/huskysoft/interviewannihilator/model/UserInfo.java
	InterviewAnnihilatorTest/src/com/huskysoft/interviewannihilator/model/UserInfoTest.java