0.pre7.86.flaky7.3:

0.pre7.86.flaky7.3:
	(This version cross-compiles all the way up to target-sxhash,
		where it dies with some sort of bug in &OPTIONAL
		arguments in FLET.)
	s/physenv-function/physenv-lambda/
	PHYSENV-LAMBDA is read-only.
	PRE-PHYSENV-ANALYZE-TOPLEVEL does COMPUTE-CLOSURE on all
		the LETs of each CLAMBDA.
		PREALLOCATE-PHYSENVS-FOR-TOPLEVELISH-LAMBDAS, which
		is supposed to play the same role, does not. What
		bozo wrote that?:-( Ahem. So..
	..Since there's never a good reason to call COMPUTE-CLOSURE
		on CLAMBDA without calling it on its LETs as well,
		and since I've demonstrated that it's an attractive
		nuisance, I'll try to make it less attractive, by
		making COMPUTE-CLOSURE automatically run over all the
		the LETs, and moving the old COMPUTE-CLOSURE code into
		an FLET hidden by the new COMPUTE-CLOSURE interface.