[ZODB-Dev] removing onCommitAction

[Jeremy Hylton]

I just removed the onCommitAction() method from the head of ZODB.  It
was only used to provide a hook for the export/import implementation,
but I came up with a simpler mechanism to provide that hook.

I thought I'd mention it in case there is someone using the method that
will miss it.  I think that's unlikely, because onCommitAction() had a
fairly limited scope.  It allowed the caller to schedule a method of the
Connection to be called during the two-phase commit.  I don't think it
would make sense to call most other methods during commit, so I don't
think it's used.  I checked Zope and Products and didn't find any calls
of it.

In general, I hope we'll be able to say more about the published
interfaces of zodb in the 3.3 release.  It's often hard to tell what is
in the API because 3rd-party code is supposed to call it and what's in
the API by accident.

Jeremy