FYI: updated to latest gnulib --- almost, but not quite

[Jim Meyering]

I was going to write this:

  FYI, I've just updated coreutils to use
  the latest from gnulib, after fixing a couple of
  minor problems in gnulib.  Now, at least for me,
  "make check" and "make syntax-check" pass with this
  latest version of gnulib (on x86_64/F17 and i686/F18)

But then I saw a some new utimes-related test failures.
And again.  But not every time.

I saw failures on 2 of 3 "make -j5 check" runs on
an old 2-core F18/i686+SSD/ext4.  But when I revert the last
two changes to gnulib's tests/nap.h, I saw 10 successes in a row,
so I'd revert those if I had more time now.