message: add sphinx-paramlinks and python-docs-theme in installation guide
diff: @@ -194,8 +194,10 @@ A complete configuration would be :
  Documentation
  =============
  -To build the documentation, `sphinx-doc <http://www.sphinx-doc.org>`_ and
  -`sphinxcontrib-bibtex <https://sphinxcontrib-bibtex.readthedocs.io>`_ are
  +To build the documentation, `sphinx-doc <http://www.sphinx-doc.org>`_,
  +`sphinxcontrib-bibtex <https://sphinxcontrib-bibtex.readthedocs.io>`_,
  +`sphinxcontrib-paramlinks <https://github.com/sqlalchemyorg/sphinx-paramlinks>`_ and
  +`python-docs-theme <https://github.com/python/python-docs-theme>`_ are
  required. As the documentation is auto-tested, `CGAL`_, `Eigen`_,
  `Matplotlib`_, `NumPy`_, `POT`_, `Scikit-learn`_ and `SciPy`_ are
  also mandatory to build the documentation.
  