make gummiboot kernel/distro agnostic

add hibernate option to .conf
create a fallback entry in gummiboot menu
re-add firmware to globalstorage, simplifies this module, will be needed to add more OS to gummi
Since this version actually works (the one in master is broken by the removal of the globalstorage) and I really don't see any distro not shipping gummiboot live, if they plan to use this module, I'd prefer to merge this now, until it can be properly tested to work with chroot_call.