Merge branch 'JPA' into 'grademanager_v1.0'

.gitignore

.idea/dbnavigator.xml

.idea/jpa-buddy.xml

.idea/misc.xml

.idea/uiDesigner.xml

.idea/vcs.xml

.idea/workspace.xml

pom.xml

src/main/Application.java

src/main/JpaService.java

src/main/abstractClasses/UniversityMember.java

src/main/classes/Course.java

src/main/classes/CoursesOfStudy.java

src/main/classes/Enrollment.java

src/main/classes/Lecturer.java

src/main/classes/Student.java

src/main/enumeration/CourseType.java

src/main/enumeration/Degree.java

src/main/enumeration/ExamType.java

src/main/enumeration/FieldOfStudy.java