add doc for extra field
diff --git a/Demo/pdist/cvslib.py b/Demo/pdist/cvslib.py
index 3e7db14..23918dc 100755
--- a/Demo/pdist/cvslib.py
+++ b/Demo/pdist/cvslib.py
@@ -39,6 +39,7 @@
 	edeleted -- true if this is an uncommitted removed file
 	ectime -- ctime of last local file corresponding to erev
 	emtime -- mtime of last local file corresponding to erev
+	extra -- 5th string from CVS/Entries file
 
 	If rseen is true: