[feature] Let the user define the keyboard shortcuts

[komen205]

I'd love to be able to change my keyboard shortcuts. And I think this would benefit other people.

For example: to go back the default key is the "escape" however it'd be nice to change it to Control + Z. Which is the key that most IDE's use.

[yfy-1997]

it's a good idea!

[skylot]

Shortcuts customization implemented by @Mino260806 in PR #1980.