* doc/Makefile.am (common_dep): Depend on $(top_srcdir)/configure not
$(top_srcdir)/configure.ac so that changes to computed variables, such
as PACKAGE_VERSION, are seen.
* tests/Makefile.am ($(srcdir)/package.m4): Likewise.
* configure.ac, doc/Makefile.am: Adjust.
* configure.ac (PACKAGE_COPYRIGHT_YEAR): New substitution, and new
config.h symbol.
Use AC_SUBST for assignments too.
* src/getargs.c (version): Use PACKAGE_COPYRIGHT_YEAR.
* doc/Makefile.am (remove_time_stamp): Include the sed invocation.
(perl -0777 -pi -e 's/.PPnId): New.
(.x.1): Use it to ignore the version control revision.
* doc/common.x, doc/bison.x: New.
* doc/Makefile.am (bison.1, .x.1): New.
The code is taken from autoconf-2.61/man/Makefile.am.
* configure.ac: Look for help2man.
Changes in response to error report by S. Eken: GLR mode does not
(yyfill): New function to copy from stack tree into array
(yyuserAction): Modify to allow incremental move of semantic values
to rhs array when in GLR mode.
Define YYFILL to use in user-defined actions to fill semantic array
(yyresolveStates): Use X == NULL for pointers, not !X.