- prepare ISO images in a way that allows hybrid ISO's which boot
  via EFI. There is some magic involved here and we are still not
  there. In order to make it work it's required to have two iso
  meta data blocks whereas one is used as real iso header providing
  boot entries for syslinux and efi-boot as well as the optional
  legacy bios based partition table for hybrids and the other one
  is used to place a gpt partition table to allow this iso to be
  seen as a disk when booting it as disk over EFI