Fix InMemoryRepoImplementations

Make them Entities and set up Tables

Create Class IDableKey

See merge request paysafe-interns-valentin-2023/paysafe-interns-valentin-martin/student-managment/filip-filchev-student-management-2023!8

Add is a field in every DefaultIDable
Make it the Key of the Map in the Generic IdableRepo
Fix UnitTests accordingly
Now GradeTable and Course Classes are not Dependeble on the Student and Course Classes
They just hold a IdableKey that is just a Long

Add Create Dtos

See merge request paysafe-interns-valentin-2023/paysafe-interns-valentin-martin/student-managment/filip-filchev-student-management-2023!7

Add Creational Dtos and fix every creational method
Fix Unit Tests Accordingly

Add Unit Tests

See merge request paysafe-interns-valentin-2023/paysafe-interns-valentin-martin/student-managment/filip-filchev-student-management-2023!6

Add @BeforeEach
Add Parametarized

More or less Unit Tests are done

Fix Average

See merge request paysafe-interns-valentin-2023/paysafe-interns-valentin-martin/student-managment/filip-filchev-student-management-2023!5

Finalize Gradle Homework

See merge request paysafe-interns-valentin-2023/paysafe-interns-valentin-martin/student-managment/filip-filchev-student-management-2023!4

Add Default Idable

See merge request paysafe-interns-valentin-2023/paysafe-interns-valentin-martin/student-managment/filip-filchev-student-management-2023!3

Generify Repositories and Services

See merge request paysafe-interns-valentin-2023/paysafe-interns-valentin-martin/student-managment/filip-filchev-student-management-2023!2

They are optimized(extend the Default Generic Service Implementation)
Fix Administartion Service and Grade Sergice accordingly

Make all Repositories just extend the Default Generic Implementation

Merge Final Changes to Project from Gradle Homework

See merge request paysafe-interns-valentin-2023/paysafe-interns-valentin-martin/student-managment/filip-filchev-student-management-2023!1

Move all Grade Logic to them - saving, calculating average, adding a new Grade