optimized method remove in class Problem
optimized method remove in class ProblemCatalog
in class Answer changend name from method getAnswerValue to isCorrect
changed tests to work with new classes
Modified Files:
src/java/de/fhworms/ztt/ox/examrepository/Answer.java
src/java/de/fhworms/ztt/ox/examrepository/Problem.java
src/java/de/fhworms/ztt/ox/examrepository/ProblemCatalog.java
src_test/java/unit/de/fhworms/ztt/ox/examrepository/AnswerTest.java
