deprecate Test Suite 1.0

If the response to bugs in the 1.0 Test Suite is "that's fixed in the
3.0 Test Suite", then presumably we should put a warning on TS 1.0,
saying that it's not maintained and that, for testing an XQuery 1.0
processor, TS 3.0 is better than TS 1.0.

(Note that https://www.w3.org/XML/Query/#hardcore still links to TS
1.0. It also says that TS 3.0 "is for people implementing XQuery 3,
XPath 3, Functions and Operators 3 and related specifications", which
suggests (by omission) that it isn't useful for people implementing
XQuery 1.0, when in fact it's now *more* useful for that purpose than
TS 1.0.)

-Michael