Redirect Python API documentation to new Sphinx-generated pages

With 5.1.0-m1 the epydoc has been deprecated from the build so the old API
documentation links are obsolete and need to be redirected to the new
Sphinx-generated API documentation. A specific extlink is added to point at
this Python-generated documentation.
Merge pull request #1011 from sbesson/sphinx-api

Redirect Python API documentation to new Sphinx-generated pages
Update auto-generated properties

Repository: openmicroscopy/ome-documentation
Already up-to-date.

Generated by OMERO-5.1-latest-docs-autogen#173 (http://ci.openmicroscopy.org/job/OMERO-5.1-latest-docs-autogen/173/)