Instead of having separate copies of the gssapi and rpcsecgss
	header files, or depending on the Kerberos gssapi header,
	locate the headers now installed with the libgssapi and librpcsecgss
	libraries.

	Remove local copies of the gssapi and rpcsecgss header files.

	This depends on the configure_use_autotools patch.

	* configure.in etc
	Consolidate some of the Kerberos checking instead of repeating
	the same things for MIT and Heimdal.
	Also adds more checks to distinguish 32-bit from 64-bit
	(mainly for gssapi.h)
	Fix svcgssd Makefile so make TOP=../../ works correctly there.
	Enable running a modern autoheader.
	* utils/gssd/gss_oids.c: Use correct OID value for SPKM-3
	* utils/gssd/gss_util.c: Fix build with older MIT releases that do not define GSS_C_NT_HOSTBASED_SERVICE
	* utils/gssd/write_bytes.h, support/include/gssapi/gssapi.h:
	Length of gss_buffer_desc is a size_t which is 64-bits on a
	64-bit machine.  Kernel code expects 32-bit integer for length.
	Coerce length value into a 32-bit value when reading from or
	writing to the kernel.
	Change gssapi.h to use datatype size values obtained from
	configure rather than hard-coded values.
	* utils/idmapd/idmapd.c: The EV_INIT check here was wrong, and was
	causing idmapd to become unresponsive to server requests after
	receiving a sighup.
	* utils/idmapd/idmapd.c: Idmapd should flush the server id<->name
	caches when its started.