Enhancements:
- Note editor: placed last modification date under the creation date for easier comparison.
- Note editor: activating links with Ctrl+Click.
- Updated translations.
- Note editor: F3 and Shift-F3 keys for find next/previous were not working (regression).
- Note editor: creation and modification time labels were not updated on Ctrl+S.
- Note editor: the "Note saved" message on Ctrl+S was not always visible.
- Note's last modified date always changed if note font was the same as the configured monospace font.
- Replaced confusing error message on trying to import a non-existent .db notebook file with a more user-friendly one.