[plt-scheme] oops regarding continuation comparison!

PLT peeps-

Hopefully I can cut you off at the pass; looking over the documentation 
again, I see that there *is* a CONTINUATION-MARKS procedure already 
provided, so I have my mapping from K to its marks!

On a tangent note: why does the manual call it a "set of continuation 
marks" ?  Isn't order significant in the data structure, and thus the 
word "sequence" would be more appropriate than set?  Of course, now 
continuation-set is part of the described interface, which is 
unfortunate.  But maybe that could be changed...

-Felix