breaking the client loop.

Cleaned up trailing whitespace.

hard to turn back on when it's needed, although, at that poiint, it
still might not be enough. :)

Object state management wasn't dome correctly when classes
  implemented custom _p_deavtivate methods.
  (https://bugs.launchpad.net/zodb/+bug/185066)

See https://bugs.launchpad.net/zodb/+bug/459889

data.  (This sometimes caused an AssertionError in
Connection._setstate_noncurrent.)

passed a tid older than anything in changes but newer than
anything in base.

test into an automated test, and included Chris Wither's repozo fix
(as monified by Godefroid Chapelle) to avoid a deprecation warning.

Bug fixed:
- Internal ZEO errors were logged at the INFO level, rather
  than at the error level.

- zope.testing was an unnecessary non-testing dependency.

Bug Fixed:

History support was broken when using stprages that work with ZODB
  3.8 and 3.9

of md5 support to avoid a deprecation warning.  I would love to
reapply 105888 (from the 3.9 branch) when there is an adequate test.
This can be achived through a pretty straightforward conversion of the
existing manual repozo test to an automated test.

Bugs Fixed:
  2 BTree bugs, introduced by a bug fix in 3.9.0c2, sometimes caused
  deletion of keys to be improperly handled, resulting in data being
  available via iteraation but not item access.

generic dostore() method instead of writing a transaction manually.

- make testrepozo.py runnable from a buildout setup
- fix deprecation warning from repozo.py under Python 2.6

hangs under extreme conditions.

  unnecessarily blocked other activity.

  ZEO manages a separate thread for client network IO.  It created
  this thread on import, which caused problems for applications that
  implemented daemon behavior by forking.  Now, the client thread
  isn't created until needed.