This directory emulates the /usr/include function when
	compiling what could be called 'out of kernel' code.
	IMPORTANT! Symbolic links to sys/foo include files
	must be retained. We don't muck around with more than
	one version of each include file!

	#include <machine/foo.h> is specially treated. Instead
	of linking 'machine' as include/machine a a path is
	added as an -I flag that points at the corresponding
	arch/${MACHINE}/include directory. This directory then
	has a symbolic link machine that points to itself '.'.


	(pefo)