* alocal.in: Use Automake::Configure_ac. ($configure_ac): Delete. (scan_configure): Adjust use of find_configure_ac; * automake.in: Use Automake::Configure_ac. ($configure_ac): Delete. (scan_autoconf_files): Adjust use of find_configure_ac; * lib/Automake/Configure_ac.pm: New file. * lib/Automake/General.pm (find_configure_ac): Delete. Now replaced by Automake::Configure_ac::search_configure_ac. * lib/Automake/Makefile.am (dist_perllib_DATA): Add Configure_ac.pm. * lib/Automake/Variable.pm: Use Automake::Configure_ac. (require_variables): Adjust use of $configure_ac.