bzip2 support

[Glenn McGrath]

Hi

I have been working on bunzip2 support for busybox, it compiles to 19kB, i
was thinking it may be usefull if it was also in grub.

When booting linux it could make it possible to compress the kernel and fs
images with bzip2, so the size should be worth it if used.

I can see that it should go into grub_open, but im not sure how to make it
play nice with gunzip compression that is now disabled for the initrd....

Im thinking it would be best to change NO_DECOMPRESSION to
NO_GUNZIP_DECOMPRESSION, or better still just NO_GUNZIP and then i could
have NO_BUNZIP2 for bzip support.

Does this sound like a good idea, if so anyone anyone have advice about a
good way to tackle it.


Glenn