0.6.11.17:

0.6.11.17:
	(like the changes in 0.6.11.13, except for -UNION this time
		instead of -INTERSECTION)
	converted SIMPLE-/COMPLEX- -UNION to -UNION2
	The old UNION :COMPLEX-UNION and UNION :SIMPLE-UNION methods
		go away in favor of TYPE-UNION and TYPE-UNION2 logic
	renamed old 2-arg TYPE-UNION to TYPE-UNION2, and revised
		it to be more like TYPE-INTERSECTION2
	defined new &REST-arg TYPE-UNION similar to the &REST-arg
		TYPE-INTERSECTION defined in 0.6.11.13
	made some old TYPE-UNION calls use &REST-arg generality
	MAKE-UNION-TYPE-OR-SOMETHING goes away in favor of new
		TYPE-UNION.
	VANILLA-UNION becomes HIERARCHICAL-UNION2.
	removed support for pre-ANSI SATISFIES types in CTYPEP