Switch to openstackdocstheme 2.2.1 and reno 3.1.0 versions. Using
these versions will allow especially:
* Linking from HTML to PDF document
* Allow parallel building of documents
* Fix some rendering problems
Update Sphinx version as well.
Disable openstackdocs_auto_name to use 'project' variable as name.
Change pygments_style to 'native' since old theme version always used
'native' and the theme now respects the setting and using 'sphinx' can
lead to some strange rendering.
openstackdocstheme renames some variables, so follow the renames
before the next release removes them. A couple of variables are also
not needed anymore, remove them.
See also
http://lists.openstack.org/pipermail/openstack-discuss/2020-May/014971.html
Change-Id: Ia7f902cce276b8e9bbc62a6f75e123521e471289
Update docs building:
* Switch to sphinx-build
* Update requirements for Sphinx and openstackdocstheme for
python 3, create doc/requirements.txt, switch to openstackdocstheme
from obsolete oslosphinx
* Remove unneeded doc and translation sections from setup.cfg
* Remove install_command, it's unneeded, the default is fine.
* Move constraints into deps, use TOX_CONSTRAINTS instead of obsolete
UPPER_CONSTRAINTS
* Switch to hacking 3.0, fix problems found
Change-Id: I44d09a65349a1d9b564e69a7fc32eb435446245c
Andreas Jaeger