prefix - prefix: refine __pr_penalty() DEBUG, some more docs

Log Message:
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refine __pr_penalty() DEBUG, some more docs

Modified Files:
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prefix:
README.txt (r1.7 -> r1.8)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/prefix/prefix/README.txt.diff?r1=1.7&r2=1.8)
prefix.c (r1.33 -> r1.34)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/prefix/prefix/prefix.c.diff?r1=1.33&r2=1.34)