keymap: Make acceptable by Xwayland
Xwayland is more strict about accepting key maps than Wayland, and it also fails silently. Instead of fixing the other parts of the stack to reshape accepted Wayland key maps into acceptable Xorg key maps, this patch makes Squeekboard serve the maximum compatibility version in the first place.
Compatibility not actually guaranteed, that's purely observational.
Works around #168 (closed)
UPDATE: Now using as many key maps as needed, knowing that Xorg can accept only a bit fewer than 250 keys in each.
Edited by Dorota Czaplejewicz