With old GS/GJS, some GType names were generated from class names without sanitizing it (e.g. Menu.ActionButton).
Instead of defining all GType names, sanitize all class name as it was GType name, and let GJS generated GType name securely when it is necessary.
Fix#46.
Array is more semantically appropriate.
For example 2 actions may have the same translations (error of a translator). With an object (or a map), only the second would be displayed, which is problematic to alert to the problem.
Additionally, handle the case where some GSettings keybinding values are empty.