(AC_OUTPUT, AC_OUTPUT_HEADER): Add an env var

 (AC_OUTPUT, AC_OUTPUT_HEADER): Add an env var
	CONFIG_STATUS to allow overriding the name of config.status.
 (AC_TEST_PROGRAM): Add missing newline.
	Always include 'fi' for cross-compiling if.
	From Jim Meyering.
Make default cache file ./config.cache,
	so PATH is not used by "." command.  From Jim Meyering.
Rename some internal macros.
	Give the diversions symbolic names.
	(AC_ARG_ENABLE, AC_ARG_WITH, AC_ENABLE_INTERNAL, AC_WITH_INTERNAL):
	New macros.
	(AC_PARSEARGS): Print --with and --enable help strings.
	(AC_ENABLE, AC_WITH): Make wrappers around _INTERNAL functions.
	Mark obsolete.
	(AC_PREPARE): Execute any saved up --with or --enable code.