Release PyPi Instruction

Instruction to release pyclustering library to PyPi repository:

1. Check version in setup.py and update it if it is required.
2. Check DOI link (README.rst, PKG-INFO.rst) and update it if it is required.
3. Check description PKG-INFO.rst and update it if it is required.
4. Generate doxygen documentation and deploy it to github pages.
5. Add core binaries to the library from cloud.
6. Create pypi file description:

$ touch ~/.pypirc
$ nano ~/.pypirc

7. Add following description:

[distutils]
index-servers=
    testpypi
    pypi

[testpypi]
repository = https://test.pypi.org/legacy/
username = <username>
password = <password>

[pypi]
repository = https://upload.pypi.org/legacy/
username = <username>
password = <password>

8. Check setup file:

$ python3 setup.py check -r -s

9. Create distributive:

$ python3 setup.py sdist

10. Upload to test repository:

$ twine upload dist/* -r testpypi

11. If everything is ok on test page then upload it to legacy:

$ twine upload dist/* -r pypi