bug#20551: Missing dokumentation for weak hash tables

Weak hash tables has an undokumented constraint in order for it to work. The key of a weak key value table / double weak table cannot be part of the value and expect the behavior in the current dokumentation to apply,, and vice verse for weak value tables. /Stefan

bug#20546: Syntax bug in master branch (till d99fedc5fd38c0)

I'm using master branch (till d99fedc5fd38c0), and I found this code can't run in 2.1, but works in 2.0: -code--- (define-syntax define-art (lambda (x) (syntax-case x () ((_ name) (identifier? #'name) #`(begin (defin