- make sure module-init-tools is part of the bootstrap list
  for openSUSE 12.3 images. Otherwise kmod-compat ist installed
  which is incompatible with the kernel packages and causes
  a zypper provides error
- search for the grub2 mkimage tool. the tool has been renamed
  in openSUSE 12.3 thus we have to find it and can't rely on
  the name
- print warning if installed isohybrid does not support EFI