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

* bootstrap.conf (gnulib_modules): Add signal, stdint.
* lib/cmpbuf.c (SA_RESTART, SA_INTERRUPT): Remove definitions.
(SIZE_MAX, PTRDIFF_MAX): Likewise.
Include <stdint.h>.
* src/system.h (WEXITSTATUS, WIFEXITED): Remove definitions.
(SA_RESTART, SA_INTERRUPT): Likewise.

* src/system.h: Include <sys/wait.h> unconditionally,
now that gnulib guarantees its presence.
* lib/cmpbuf.c: Likewise for <unistd.h> and <inttypes.h>.

Avoid a warning from automake:
lib/Makefile.am:23: AM_CFLAGS multiply defined in condition TRUE ...
lib/gnulib.mk:30: ... `AM_CFLAGS' previously defined here
lib/Makefile.am:18:   `lib/gnulib.mk' included from here

* lib/Makefile.am (AM_CFLAGS): Append $(WARN_CFLAGS) and
$(WERROR_CFLAGS), i.e., use "+=", not "=".
This was introduced via 2009-12-17 commit e58efa5b
"build: enable warnings and -Werror.",
but fortunately is not a bug, because the definition
it would have overridden was always empty.

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

* src/Makefile.am (AM_CFLAGS): Enable warnings and -Werror.
Set to this: $(WARN_CFLAGS) $(WERROR_CFLAGS)
* lib/Makefile.am (AM_CFLAGS): Similarly, but use this:
$(GNULIB_WARN_CFLAGS) $(WERROR_CFLAGS)
* configure.ac (GNULIB_WARN_CFLAGS): Don't turn off -Wuninitialized.

* lib/cmpbuf.c: Include "intprops.h" rather than open-coding macros
like TYPE_SIGNED and TYPE_MINIMUM.

* lib/prepargs.c (prepend_default_options): Remove useless cast.
* cfg.mk (local-checks-to-skip): Remove sc_cast_of_x_alloc_return_value.

Many are now obtained via bootstrap from gnulib.
Others (ms/) were not being maintained.