* configure.in: Use the AC_PROG_CPP macro, and then use the CPP

* configure.in: Use the AC_PROG_CPP macro, and then use the CPP
	variable to scan the machine and system description files.

	* configure.in: Use the AC_HAVE_HEADERS to check for sys/timeb.h,
	so that getdate.y builds correctly.

	* configure.in (tempcname): Change this to "conftest.c", so it will
	work properly on systems with short filenames; this is the name
	autoconf uses.

	* configure.in: Also detect the availability of dup2 and
	gethostname.

	* configure.in: Use the AC_ALLOCA test.
	* Makefile.in (ALLOCA): New variable, to be set by ./configure.
	(lib-src/Makefile): Edit the value of ALLOCA into lib-src/Makefile.

	* Makefile.in: Add autoconf cookies so that the configure
	script can comment out sections of path variable definitions to
	choose between the installable configuration and the run-in-place
	configuration.
	* configure.in: Add new option `--run-in-place', to select the
	run-in-place path definitions.

	* configure.in: Add a clause to the big configuration name case
	for the NeXT machine.