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.

$ sudo apt-get install graphviz
$ sudo apt-get install texlive
$ doxygen docs/doxygen_conf_pyclustering

$ cd ../
$ mkdir pyclustering-website
$ cd pyclustering-website
$ git clone https://github.com/pyclustering/pyclustering.github.io.git .
$ cp -r ../pyclustering/doxygen_docs docs/<library_version>
$ git commit . -m "[docs] Upload documentation for library version <library_version>."
$ git push

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