proposed bootstrap changes

[Richard Kenner]

    Here is my fixed rule (example).  Should this work OK?

    restage2:
	-test -d stage2/. && (cd stage2; tar -cf - .) | tar -xpf -
	-rm -rf stage2 stage3 stage4 stage2_build stage2_copy
	$(MAKE) LANGUAGES="$(LANGUAGES)" stage2_build

I don't like this because of the tar.  It means you potentially
lose date information (I know you're not supposed to), but also run the
risk of a disk filling since you have can have two copies for a while.

I'd prefer to run a loop that does recursive mv's.