Support for Keyboard Binding "Themes"

First of all: Thank you very much for creating this project! ❤️

I would like NotepadNext to have support for (at least some) Emacs keybindings, at least the most basic ones (^f/b: forward/backward, ^n/p: next/previous line, Meta-f/b: next/previous word etc.), but ideally also including key sequences like ^x^s: save file.

As everyone and their dog wants to use their favorite set of keybindings, it would probably make sense to have support for keyboard binding "themes", with 3 predefined themes: Notepad++, Emacs, vi. Users should be able to modify existing themes and save them under a selectable name.

On the one hand, this wishlist bug seems to be relevant only for a distant future version of NotepadNext, on the other hand, it is something so fundamental that it would be difficult to change later, so that I rather mention it now.

Thanks for your consideration!