[CM] copy-list, guile and r5rs

[Orm Finnendahl]

Hi Rick,

I stumbled on some problem with copy-list in level1.scm:

copy-list doesn't actually do a copy in guile (at least on my
machine). To use (append lis '()) for list copying seems to get
optimized away despite r5rs' specification of append and the call
returns the same object instead of a copy.

I don't know if that is any problem in your code but thought to let
you know anyway.

--
Orm