master
create: Group.java, School.java, Trainee.java, TraineeBidiMap.java, TraineeMap.java, TraineeMultiValuedMap.java, TraineeQueue.java, TrainingErrorCode.java, TrainingException.java
create: TestGroup.java, TestSchool.java, TestTraineeBidiMap.java, TestTraineeMap.java, TestTraineeMultiValuedMap.java, TestTraineeQueue.java