PARKA no longer in mcl contrib

[straz@cambridge.apple.com (Steve Strassmann)]

At the author's request, I've removed the PARKA knowledge
representation system from the MCL contrib directory...

 >  Steve, 
 >
 >  Would you do me a favor and remove the PARKA code from the contrib
 >directory on the cambridge archive.  It's hopelessly out of date and
 >I'd hate for anybody to get that version and start asking me questions
 >about it....
 >
 >  Thanks...