0.7.13.7:

0.7.13.7:
	Fix really stupid bug in CONS :SIMPLE-UNION method
	... don't mix the CDR type into the CAR type
	While I'm there, make the CONS :SIMPLE-UNION method smarter
	... canonicalize unions of (CONS A D) with (CONS A' D'), where
	A subtypep A', to
		(OR (CONS A (OR D D')) (CONS (AND A' (NOT A)) D'))
	the point being that this is then in a form that can be	further
	canonicalized when more CONS types come along. 	This fixes about
	5 bugs from pfdietz's suite.