Binpickle

This just updates to test on Python 3.9 and include the tests in the source distribution (so they can be run as a part of downstream Conda buil processes).

Merged PRs

* Update to Python 3.9 and drop Conda (16) mdekstrand

Fix a small issue preventing multiple closing.

This fixes a bug in Blosc compression support, that probably goes back to the first version of binpickle.

This bug only caused saving to fail; it did not cause data loss or corrpution.

Merged PRs

* Fix Blosc splitting to use bytes, not items (14) mdekstrand

This release expands codec support:

- `Chain` allows multiple codecs in sequence
- Codecs can be selected per-buffer with a codec selector function
- Numcodecs support is added

No code changes here - only build changes, particularly to the Conda packages, to enable installation without the `conda-forge` channel.

This release has two notable changes:

- Add GZ compression, powered by the standard `zlib` module, and make it the default
- Make Blosc optional

To install from PyPI with Blosc support, run:

pip install binpickle[blosc]

This allows the default install to work without needing to compile Blosc, since they don't ship binary wheels on PyPI. This is especially useful when using Binpickle primarily for shared memory.

The Conda packages will continue to depend upon `python-blosc` by default. We recommend using Blosc for most common usage.