- Remove fossil tests.

these must be controllable separately

(the tests themselves still aren't being run; we need decent
save/restore behavior from the logging package to do this properly)

later

See http://zope.org/Collectors/Zope/1289.

Avoid the monkey patch by creating a subclass of Connection and
installing it as the klass attribute of ZODB's DB class.  I think this
works correctly in conjunction with Zope configuration (the tests
pass) -- but I'm not qualified to say for sure.

Rework the logic of MountConnection as part of the restructuring.  The
_root_connection attribute always points to the root, never to None;
so the root object points to itself.  This change necessitated a
chance in DBTab.ClassFactories.  Add some comments there to explain
what's going on.

XXX The close() method on MountConnection is re-implementing two
methods in modules.  If those implementations change, it would need to
change, too.  We ought to find a better way to integrate it.

XXX Perhaps the mounted connection stuff should be folded into ZODB
proper.

just like it does not exist

the signal handler installation is abstracted in the same way

  loosely coupled and re-uses the shared logging configuration more
- replace uses of zLOG with logging

no equivalent

hack it