[Fedora-livecd-list] updated liveusb,sh

[Fred J. Bourgeois, III]

I made some changes to Jasper Hartline's excellent liveusb.sh
script, mostly to make sure that files are taken from repos and
not a (possibly different distro) local installation.  Also, my
version inlines the calls to fdisk and grub, and adds default
values for PACKAGES, GROUPLIST, ROOTPATH.  I hope this is okay? 
These changes were sparked because I am still running FC5 on my
main machine, but want to build an FC6 flashdrive system.  (I
also "preserve" the yum cache to take advantage of my local repo,
something you may not want to do in the release version.)

I am continuing to work on improving this script, but you can see
my current version at
    ftp://ftp.applios.net/pub/fjb/LiveUSB/liveusb.sh
Any feedback would be appreciated!

Thanks,
Fred J. Bourgeois, III