coreutils-5.97 released

This is a stable release.
Two points are worth special mention.

I built it using autoconf tools from cvs of June 23.  Normally, I would
not use development infrastructure to create a stable coreutils release,
but since autoconf-2.60 is so near, and since I did it for 5.96,
too, I think it's a good mix of being worthwhile and not too risky.
It's worthwhile to get more exposure for recent autoconf changes, yet
since autoconf is in prerelease, bugfix-only mode, it is not too risky.

I added chgrp's --preserve-root and --no-preserve-root options.
So now, chgrp supports those options, as it was documented to do,
and just as chmod, chown, and rm do.

Thanks to Paul Eggert and Ralf Wildenhues for their help.
As usual, see the ChangeLog files for full credit.

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The GNU coreutils package contains the following programs:

  [ basename cat chgrp chmod chown chroot cksum comm cp csplit cut date dd
  df dir dircolors dirname du echo env expand expr factor false fmt fold
  ginstall groups head hostid hostname id join kill link ln logname ls
  md5sum mkdir mkfifo mknod mv nice nl nohup od paste pathchk pinky pr
  printenv printf ptx pwd readlink rm rmdir seq sha1sum shred sleep sort
  split stat stty su sum sync tac tail tee test touch tr true tsort tty
  uname unexpand uniq unlink uptime users vdir wc who whoami yes

The coreutils package replaces/unifies the fileutils, sh-utils, and