* doc/diffutils.texi (copying): Relax restriction on front-cover
and back-cover texts (just as m4 did here:
http://git.savannah.gnu.org/cgit/m4.git/commit?id=ee1e92ec).
Reported by Santiago Vila.  Fix suggested by Eric Blake.

This makes the .texi basename the same as the package name,
which is consistent with most other GNU packages.
* doc/diffutils.texi: Rename from...
* doc/diff.texi: ...removed.
* doc/Makefile.am (info_TEXINFOS): Reflect name change.
(diffutils_TEXINFOS): Likewise.
* cfg.mk (gendocs_options_): Remove this customization.  It is no
longer needed, now that the .texi name matches that of the package.
* man/Makefile.am ($(dist_man1_MANS)): Remove now-unnecessary sed
filter.
* README: Update references to diffutils.texi etc. here, too.
* .gitignore: Update here, too.
Suggested by Karl Berry.

* doc/diff.texi (diff Options): Document -L.

Convert using this command:
perl -pi -e \
  's/(\@option{-.}) or (\@option{--.*?}) option/$2 ($1) option/' \
  doc/diff.texi
Then convert some more with this:
perl -pi -e \
    's/the (\@option{-.}) or (\@option{--.*?})$/the $2 ($1)/' \
  doc/diff.texi
Then convert more manually.

Suggested by Dan Jacobson

Run "make update-copyright", so "make syntax-check" works in 2011.

* doc/diff.texi: Update to use GFDL version 1.3.

Use this command:
git ls-files |grep -vE '^(\..*|COPYING|gnulib)$' |xargs \
env UPDATE_COPYRIGHT_USE_INTERVALS=1 build-aux/update-copyright

* doc/diagmeet.note: Use no TABs.
* ms/config.sed: Use TAB-space, not space-TAB in [].
* cfg.mk (local-checks-to-skip): Remove sc_space_tab.

* doc/diff.texi: Remove $Id$.
* cfg.mk (local-checks-to-skip): Remove sc_prohibit_cvs_keyword.