[Spambayes] merging tomorrow--big code changes

[Jeremy Hylton]

May I suggest changing the name of the persistent module?  I'm just
trying to avoid confusion with the ZODB-based persistence approach.
In that world, Persistence and Persistent mean something quite
different than a class with load() and store() methods.  The training
stuff also seems independent of the load/store part.

Perhaps there should just be a storage module with PickledClassifier
and DBDictClassifer.  The classify() method could be moved into 
classifer.Classifer.  (This seems like the natural place.)  Then the
abstract class isn't really necessary, since it only defines two
methods that most be overridden anyway.

Jeremy