Look at ../../../docs/index.html under the "GRUB2 payload" section to see
how the following files were generated:

 * dvorak.gkb
 * ukdvorak
 * ukdvorak.gkb
 * ukqwerty
 * ukqwerty.gkb
 * usdvorak
 * usqwerty
 * usqwerty.gkb

The files listed above are made available in the public domain (the information in them is public knowledge. copyright is pointless). Use them as you wish.