This patch publishes the work done until now
for Python 3.0 compatibility. Still a lot
to be done.

When possible, we use 3.0 features in Python 2.6,
easing development and testing, and exposing internal
changes to a wider audience, for better test coverage.

Some mode details:
http://www.jcea.es/programacion/pybsddb.htm#bsddb3-4.7.2