Need keyamp support for worldwide contributions

[ygbourhis]

Currently snakeware only uses US qwerty keymap. We should be able to set the keymap easily either once booted, or at boot time via grub, or at build. Without different keymaps, it will be hard to get contributors from outside US (I'm French, I'm a python developer, but once in the snakeware python shell, it is unusable without brain torture to remap mentally...).