Merge branch 'feat/concurrent-loading-album' into 'dev'

src/main/java/NTNU/IDATT1002/App.java

src/main/java/NTNU/IDATT1002/controllers/DataExchange.java

src/main/java/NTNU/IDATT1002/controllers/ExploreAlbums.java

...in/java/NTNU/IDATT1002/repository/AbstractRepository.java

src/main/java/NTNU/IDATT1002/repository/AlbumRepository.java

.../java/NTNU/IDATT1002/repository/GeoLocatioRepository.java

.../java/NTNU/IDATT1002/repository/HistorgramRepository.java

src/main/java/NTNU/IDATT1002/repository/ImageRepository.java

src/main/java/NTNU/IDATT1002/repository/LoginRepository.java

...in/java/NTNU/IDATT1002/repository/MetadataRepository.java

src/main/java/NTNU/IDATT1002/repository/Repository.java

src/main/java/NTNU/IDATT1002/repository/TagRepository.java

src/main/java/NTNU/IDATT1002/repository/UserRepository.java

src/main/java/NTNU/IDATT1002/service/AlbumService.java

src/main/java/NTNU/IDATT1002/service/TagService.java

src/main/resources/NTNU/IDATT1002/explore_albums.fxml

...t/java/NTNU/IDATT1002/repository/AlbumRepositoryTest.java

...t/java/NTNU/IDATT1002/repository/LoginRepositoryTest.java