[Zope] using the Session Data Object hooks

[Dennis Allison]

Thanks Chris.  I'll take a look.  I got the hooks working, sorta.  I wanted 
to use them for session tracking but 1) they are invoked pretty early--when
the session is created but before any session data is installed and 2) users
don't really every logout (they just go elsewhere) and so the session objects
remain around and never get closed out.  Yuck.  Anyhow, for my purposes I
will need to examine them periodically, cull out the old ones, etc.  Still,
it's a nice feature.