progress(1) in /rescue

[Rin Okuyama <rokuyama%rk.phys.keio.ac.jp@localhost>]

Hi,

I'd like to add progress(1) into /rescue, which costs only ~6KB on,
e.g., m68k. This should greatly reduces stress for someone who has to
recover the system from tarballs. Objections?

Thanks,
rin