ComboBox, SystemProperties, Converter, Moved ConfirmButton and ConfirmDialog
ComboBox is the first Version of Implementation of an JComboBox<String> in our Engine. ConfirmButton and ConfirmDialog were sent to the package comp, because it's a better place for them than in gui. Converter is a new class containing some helping methods for converting String [] in List<Strings> and the way round. I replaced MouseListener with MouseAdapter in List because of faster reading. The Thread SystemProperties will print the System Properties at the Beginning of the Game after being able to run Main.