Current version incompatible with poetry about bitshuffle HOT 1 OPEN

@danielemichilli @jrs65 -- looking into this issue and here are some observations.

• The issue is not pyproject.toml -- it is set up with sufficient parameters.
• The issue arises from the current layout of setup.py itself. You can replicate this issue by simply following the commands below:

cd bitshuffle
docker run -it -v $(pwd):/bitshuffle python:3.7-slim python /bitshuffle/setup.py --help

Traceback (most recent call last):
  File "/bitshuffle/setup.py", line 13, in <module>
    from Cython.Compiler.Main import default_options
ModuleNotFoundError: No module named 'Cython'

You need Cython installed in the environment to even evaluate the install and setup directives. This breaks any setup command other than install.

As a result, you cannot currently install bitshuffle locally, and even python setup.py install will fail.

Most third-party dependency resolution systems, pipx, poetry, flit etc. use egg_info to fetch metadata, build tags and dependency links for the project. Note, this is outside the purview and different from install_requires and setup_requires dependencies which are correctly defined in pyproject.toml.

I bandaid fix for this issue, is in #123

from bitshuffle.