Merged 4.1.20 changes onto trunk

[James Youngman]

I had put the findutils code changes for release 4.1.20 on a branch.
As these now seem to be stable (i.e. introduce no major problems - at
least, nobody has told me of any) I have merged this code onto the
trunk.  I have also made some updates to the code to be compatible
with some recent changes to gnulib (notably relating to the function
call interface changes in gnulib's human.c).

If you are building the findutils code from CVS, and normally use the
trunk, you will need to read README-CVS (which explains how to add in
a current version of the gnulib code - we no longer have a forked copy
of the gnulib code inside findutils).

At this point I plan to begin merging in bugfixes and trivial patches.
I'm not going to merge in major functional changes just yet.  The next
release should be 4.2.0 and will include the important fixes and
portability patches.  I'm not going to speculate as to when version
4.2.0 might be ready.

If you wish to track my progress, please check the "bugs" and
"patches" sections of the findutils project page of
<http://savannah.gnu.org/>.