Use case:

• Anaconda supports OEMDRV feature.
• When a user inserts a flash drive with OEMDRV label and ks.cfg on it, the kickstart is used automatically.
• I was told the feature is quite fragile, because the flash drive doesn't always get loaded in time and properly.

That's why we want an option how to add ks.cfg on installation media.

The overall idea is to create a script that patches an iso with files from overlay directory:

pungi-patch-iso [--supported=..] [--label=...] <target-iso> <source-iso> <overlay-dir>

• mount source iso
• create graft points from mounted source iso + overlay dir
• if ks.cfg is detected, patch syslinux + grub to use it
• label is copied from source iso unless --label is specified
• make the target iso bootable if source iso is bootable
• supported composes: fedora-25+, rhel-7+
• implantmd5 + supported bit (use the same as on source iso, unless overriden by --supported option)
• isohybrid support