Fixed #11 - use AlertGenerator

src/charts/ChartGUIController.java

src/core/Exporter.java

src/core/Importer.java

src/userInterface/EditController.java

src/userInterface/InsertTimeController.java

src/userInterface/Main.java

src/userInterface/ProjektFensterController.java

src/userInterface/UserInterfaceController.java