New Snapshots and diffs have been posted

The 2009-05-06 snapshot has been posted along with diffs that compare  
each document with their 2009-03-31 snapshot.
The W3C diff service choked on some of these files so this time, I  
produced diffs using hrmldiff.py.
Unfortunately, when the resulting documents were checked in, cvs  
updated the header line to insert today's date. As this only is  
affects the diff documents, and neither snapshot and correctly  
identifies the day that the diffs were checked-in, I decided to leave  
them alone even though they might be a bit confusing.
With that explanation, I suppose they may be useful to review changes  
that have ben made since the last snapshot.
thanks
-bob