This prevents a KeyError: '\x00\x00\x00\x00\x00\x00\x00\x00'

I guess there were no tests of GC.

That was made effective by recent changes in ZODB that relied more on
loadBefore for MVCC.

Oddly the change makes this loadBefore match the version it was copied
from, which github says was last changed 13 years ago. (gulp, on
multiple levels).

See: http://blog.travis-ci.com/2014-12-17-faster-builds-with-container-based-infrastructure/

Downloaded from http://downloads.buildout.org/2/bootstrap.py

Python 3 compatibility

Make the local tests use "normal" unittest conventions.