New images find their root device by looking at the CDLABEL. Since pungi
is building ISO images separately from lorax, if it uses a different ISO
Volume Label we'll end up with unbootable images.
This changes the volume labels to match what pungi uses, so both should
boot OK.
This adds the boot config files from anaconda to lorax's configdir.
They've been edited to include a '@ROOT@' placeholder, so lorax can put
the proper root=... argument in place, and to use the @VAR@ convention
everywhere (instead of some using @VAR@ and some using %VAR%).
This should probably fix EFI booting, since the EFI BOOT*.conf was
missing its root=... arg.
Also some default settings were changed in syslinux.cfg (so we don't
have to rewrite those two lines every time).
One last change - the '-magic' arg and ppc 'magic' file have been
dropped, because that's kind of silly and unnecessary.
TreeBuilder uses templates full of commands (like ramdisk.ltmpl) to
create the output tree and boot images. There are 4 arch-specific
templates, plus a bonus EFI template which can handle EFI image creation
for any arch that implements EFI.