Implement backend for question service

[Jweng88]

Question service uses mongoDB to store questions

CRUD operations:

1. Get request: Get the whole list of questions or by id with sorting, searching, filtering and pagination
2. Post request: Create a question when all fields are filled
3. Put request: Update a question when all fields are filled
4. Delete request: Delete a question with matching question id
5. Basic error handling like duplicates and missing fields