Build flags for the next version of hdf5plugin

[t20100]

Information for packaging next version of hdf5plugin:

PR silx-kit/hdf5plugin#52 and silx-kit/hdf5plugin#51 added some build options that are of importance for packaging.
Those options are:

• --openmp: Used for the bitshuffle filter
• --native: To optimize for the machine building the package
• --sse2: To enable SSE2 in the blosc filter (needs for an environment variable)
• --avx2: To enable AVX2 in the blosc filter (needs for an environment variable)
  The bitshuffle filter is using SSE2 or AVX2 with --native=True or --sse2=True and --avx2=True.

What is used to build wheels on x86_64 is:
python setup.py build --openmp=False --native=False --sse2=True --avx2=False bdist_wheel
I think you will need the same.

[tschoonj]

Thanks for the info, I will keep it in mind

[t20100]

PR silx-kit/hdf5plugin#54 also add a --cpp11=[True|False] flag for building the snappy compression in the blosc filter (which requires C++11).
Depending on the availability of C++11 in conda you also might want to set that.

For the wheels, we set it to False except for python3 on Windows where C++11 is available starting from python 3.5.

[t20100]

BTW, v2.1.0 is released and uploaded on pypi: https://pypi.org/project/hdf5plugin/2.1.0/