[IZPACK-1099] Refactor automated installations as it is (for Swing installers, but more universal)

The current state before this change has been:

- Adding the generation of auto-install.xml to the FinishConsolePanel is not possible without refactoring the implementation and API in common, because the whole implementation is bound to Swing installer classes (IzPanel).

- The created file cannot always be processed especially for createForPack constraints to UserInputPanel. If there are skipped panels due to this constraints and the installer is re-ran in a same environment with the recorded first installation it fails, because the panels with constraints like createForPack are not skipped, but there is expected and validated user input for them.

- The file dialog on FinishPanel should offer a default file name.

Should be solved herewith.