Added methods:	
	public List<ThesisDefence> getDefenceBySecretary(long secretaryId);
	public List<ThesisDefence> getFinishedDefenceBySeretary(long
secretaryId);
	public List<ThesisDefence> getDefenceByPersonnel(long personnelId, int
isHead, int isSecretary);
Added methods:
	findBySupervisorID(long supervisorId);
	findByReviewerID(long reviewerId);
	get_free_thesis();
	findByStudentID(long studentId);
	getThesisByFilter(String studyLevel);
Renamed field 'studylevel' to 'studyLevel'
Added method findByDefendedThesis(long defendedThesisId);
Modified query for method get_free_thesis();
Made revisions.
Added Interfaces for Service Layer.
Added method declarations.
Formatted code