maint: update to latest gnulib

Allows bootstrap to work on FreeBSD, where gzip doesn't have a '.'
in its version; and silences false positives in the new
'make syntax-check' rule.

* .gnulib: Update to latest.
* bootstrap: Synchronize to upstream.
* .x-sc_bindtextdomain: New exemptions.
* Makefile.am (syntax_check_exceptions): Ship new file.
* .gitignore: Regenerate per latest bootstrap, anchor entries that
are only in the root directory, and consolidate entries from other
generated .gitignore files.
* build-aux/.gitignore, m4/.gitignore, po/.gitignore: Remove from
version control, since bootstrap generates them.

.gitignore

@@ -1,3 +1,7 @@
+!/m4/compiler-flags.m4
+!/po/*.po
+!/po/POTFILES.in
+!/po/libvirt.pot
 *#*#
 *.#*#
 *.a
@@ -12,45 +16,48 @@
 .git
 .git-module-status
 .sc-start-sc_*
+/ABOUT-NLS
+/COPYING
+/ChangeLog
 /GNUmakefile
+/INSTALL
+/NEWS
+/aclocal.m4
+/autom4te.cache
+/build-aux/
+/config.cache
+/config.guess
+/config.h
+/config.h.in
+/config.log
+/config.rpath
+/config.status
+/config.sub
+/configure
+/configure.lineno
+/gnulib/
+/libtool
+/libvirt-*.tar.gz
 /libvirt-[0-9]*
+/libvirt.pc
+/libvirt.spec
+/ltconfig
+/ltmain.sh
+/m4/
 /maint.mk
+/mingw32-libvirt.spec
+/mkinstalldirs
+/po/
 /proxy/
-ABOUT-NLS
-COPYING
-ChangeLog
-INSTALL
+/tests/*.log
+/tests/nwfilterxml2xmltest
+/update.log
 Makefile
 Makefile.in
-NEWS
-aclocal.m4
-autom4te.cache
-config.cache
-config.guess
-config.h
-config.h.in
-config.log
-config.rpath
-config.status
-config.sub
-configure
-configure.lineno
 coverage
 cscope.files
 cscope.out
-gnulib/
-libtool
-libvirt-*.tar.gz
-libvirt.pc
-libvirt.spec
-ltconfig
-ltmain.sh
-mingw32-libvirt.spec
-mkinstalldirs
 results.log
 stamp-h
 stamp-h.in
 stamp-h1
-tests/*.log
-tests/nwfilterxml2xmltest
-update.log