I also plan to remove the "#ifndef _KERNEL" around sysctl.h's inclusion
   of
   
   	#include <sys/time.h>
   	#include <sys/ucred.h>
   	#include <sys/proc.h>
   	#include <vm/vm.h>
   
   It's a pain to have to remember to include these files (especially
   <vm/vm.h> just to include <sys/sysctl.h>.


i don't care about the first 3, but i definately wouldn't mind seeing
<vm/vm.h> going into <sys/sysctl.h> for now.  after 1.5 branch, i am
planning on removing <vm/*.h>.  if you make this change, please update
the documentation as such.