Merging folderstructure/onion architecture with EF Core

[tomat-suppe]

EFCore functionalities have been split between these two branches, and therefore we need to clean up the code and merge to a functional branch

[tomat-suppe]

This merge was basically impossible. Instead we have created a new branch, where we have manually merged the two branches. This new branch is called EFCoreAndRefactoring. Done by: Henriette hoes@itu.dk and Sophie Gabriela slak@itu.dk