* Saving:
- Use the Gtk::FileChooser confirm-overwrite feature
instead of our own dialog.
- Avoid warning when using Save As.
* Translations: Added Catalan (Josep Puigdemont),
Dutch (Vincent van Adrighem), Finnish (Ilkka Tuohela),
French (Benoît Dejean, Damien Durand),
Hungarian (Gabor Kelemen), Slovak (Marcel Telka),
Nepali (Pawan Chitrakar)
