message: Got rid of Cython build procedure.
diff: pip install pip --upgrade
  pip install setuptools --upgrade
  -# Install cython separately
  -pip install cython
  -
  # Install development dependencies
  cd ..
  pip install -r devrequirements.txt
  -# Compile CMBTR and ACSF extensions with cython. The .so files will be compiled
  -# during package setup
  -cd dscribe/libmbtr/
  -cythonize mbtrwrapper.pyx -X language_level=3
  -cd ../libacsf/
  -cythonize acsfwrapper.pyx -X language_level=3
  -
  # Make a source distribution
  cd ../..
  python setup.py sdist
  