Add Multiboot support

[krolmiki2011]

Hey, Can you add multiboot support like use rEFInd, above systemd, or even grub-blscfg from AUR: https://aur.archlinux.org/packages/grub-blscfg, it will make arkdep systems more exclusive.

[dennis1248]

It is on the list to add support for GRUB. Other more fringe bootloaders I am not sure about yet.