recent -last initialization changes

05/09/95 save original PATH in _probe_PATH
	 hostinfo with no args equivalent to `hostinfo type'
	 beef up library dir probe
04/01/95 use c source suffix if it still preserves the dialect
	 add hostinfo
	 add lib/hostinfo/typemap user type map
	 add sol.sun4 cpu count
	 fix C.probe to properly handle C/C++ combined compiler drivers
	 add NeXT to hostinfo
	 bummer: mach has /usr/bin/hostinfo
03/19/95 fix dialect executable test
