to avoid unnecessary calls to the persistent_id hook for objects that
we know can't be persistent.

new_oids to avoid a race.

  twice (with test)
- remove irrelevent and unused test_suite definition from testDemoStorage.py

datetime modules. :(

  keyword option can be passed to the pack method.  A false value
  prevents garbage collection.

- The FileStorage constructor now provides a boolean pack_gc option,
  which defaults to True, to control whether garbage collection is
  performed when packing by default. This can be overridden with the
  gc option to the pack method.

The ZConfig configuration for FileStorage now includes a pack-gc
  option, corresponding to the pack_gc constructor argument.

- The FileStorage constructor now has a packer keyword argument that
  allows an alternative packer to be supplied.

The ZConfig configuration for FileStorage now includes a packer
  option, corresponding to the packer constructor argument.

Added a new test class for testing packing without gc.

Moved some useful tests to PackableStorage so they are run by storages
without undo.

empty transactions.

it could be made simpler still.)

- explicit push and pop methods

- backward compatible with old behavior.

Moved size-limiting-cache feature to future release, since it

addresses some of the windows errors. (I think the remaining failures
here and in dbopen.txt have to do with the way time is used in
management of available connections.)

closed.

tests have a clean transaction state and to avoid leaving files behind.

to abort the current global transaction before and after each test and
to create a temporary test directory to run each test.

relative path, the blob machinery used relative paths, which could
lead to breakage if an application changed directories.

blobs work for large databases on systems that don't allow many
subdirectories.

rather than a file storage. This makes interactive exploration easier.
This is tested indirectly by the ConflictResolution.txt test.  I
expect more tests to take advantage of this convenience. It would be
nice to have an explicit test.

Get WeakSet from the transaction package.