Renamed some of the pages

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

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

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

...ain/java/NTNU/IDATT1002/controllers/UploadedMultiple.java

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

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

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

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

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

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

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