versions of Python.  We don't want spurious leaks when checking for
ZODB leaks.

The stdlib doctest.DocTestSuite is broken in such a way that you can't
repeat tests.  Provide an environment variable to use the doctest from
zope.testing.

repeat tests.  Provide an environment variable to use the doctest from
zope.testing.

repeat tests.  Provide an environment variable to use the doctest from
zope.testing.

(This is indirectly tested by the BTree tests.)

repeat tests.  Provide an environment variable to use the doctest from
zope.testing.

classes created on the fly are used with them. Unfortunately, UserList
and thus PersistentList have ABCs.  :(  So changed an in-test-created
class to a glbal to avoid a testing memory leak so as not to hide real
memory leaks.

repeat tests.  Provide an environment variable to use the doctest from
zope.testing.

Also did some storage server implementation cleanup, removing some
dups and folding a small module into StorageServer.py.

to decide how to write other data.

Removed untested unsupported dbmstorage fossil.

to decide how to write other data.

----------

- Shutting down a process while committing a transaction could cause
  ZEO client caches to have invalid data.  This, in turn caused stale
  data to remain in the cache until it was updated.

merges.

differences.

When an integer too large to fit in a 32-bit integer was provided as
  a 32-bit-integer BTree key or value on 64-bit machines, an
  OverflowError was raised. Now a TypeError is raised.

non-standart ;) time zones.

Cleanup trailing whitespace in verbose stats output.

between logs and ints.

  entry, the cache could be left in a stage when there is data marked
  current that should be invalidated, leading to persistent conflict
  errors.

- Invalidations of object records in ZEO caches, where the
  invalidation transaction ids matched the cached transaction ids
  should have been ignored.

- Corrupted or invalid cache files prevented ZEO clients from
  starting. Now, bad cache files are moved aside.

Cache simulation, while not perfect, seems to be much more accurate
now than it was before.

The ZEO cache trace statistics and simulation scripts have been
given more descriptive names and moved to the ZEO scripts package.