[Request] "--keymap" Support

[PJaros]

Is there any support for keymap files like https://github.com/libretro/hatari/blob/master/doc/keymap-sample.txt which then can be loaded from the command-line with --keymap <file>?

I'm using Ubuntu 18.04 and I am trying to remap the "Home", "Insert" to "PageUp" and "PageDown".