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- BREAKING CHANGE (very unlikely, though): `push`/`put` now returns the
uid of the just added item. Before it always returned `None`.
- `push` has been renamed to `put`; `push` stays as an alias, but is
deprecated and will be removed in version 4.
- `pop` has been renamed to `get`; `pop` stays as an alias, but is
deprecated and will be removed in version 4.
- Increased version compatibility with redis.py to "<2.11".
- Python 3.4 support
- More tests. Introduced tox for testing.
- Added `serializer` parameter to support custom serializers,
e.g. for automatic JSON conversion. See README for details, especially
when using Python 3.