Citra suggestion: allow hotkeys assign to unused gamepad buttons

Hello!

Recently I found, that my gamepad has more buttons than 3DS, and I see there are useful hotkeys, but they were for the keyboard only. To use them, I have to always move my hand off the gamepad to press the desired hotkey on the keyboard. That isn’t a problem when I sit on a chair being close to the keyboard. But when I sit far off the computer, for example, on a sofa? Why not allow to assign unused gamepad buttons to hotkeys too? For example, making screenshots by Citra itself (having higher quality than the game built-in screenshot makers), or toggling alternative and main speeds. Or just save/reload states. What do you think?

P.S. Off this topic: also, could be helpful to specify the default path for built-in screenshot saving with automatic naming of screenshot files, rather than manually selecting the save path every time.