Switch to newer openstackdocstheme and reno versions

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.

Remove docs requirements from lower-constraints, they are not needed
during install or test but only for docs building.

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.

Set openstackdocs_pdf_link to link to PDF file. Note that
the link to the published document only works on docs.openstack.org
where the PDF file is placed in the top-level html directory. The
site-preview places the PDF in a pdf directory.
Set openstackdocs_auto_name to use 'project' 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.

See also
http://lists.openstack.org/pipermail/openstack-discuss/2020-May/014971.html

Change-Id: Icba2725bf805f7b1d0ef7bc43a511e226852c9ef

doc/requirements.txt

@@ -1,6 +1,6 @@
-sphinx>=1.8.0,!=2.1.0 # BSD
+sphinx>=2.0.0,!=2.1.0 # BSD
 sphinxcontrib-apidoc>=0.2.0  # BSD
-openstackdocstheme>=1.32.1 # Apache-2.0
+openstackdocstheme>=2.2.1 # Apache-2.0
 
 # releasenotes
-reno>=2.5.0 # Apache-2.0
+reno>=3.1.0 # Apache-2.0

doc/source/conf.py

@@ -26,9 +26,10 @@ extensions = [
 ]
 
 # openstackdocstheme options
-repository_name = 'openstack/python-congressclient'
-bug_project = 'python-congressclient'
-bug_tag = ''
+openstackdocs_repo_name = 'openstack/python-congressclient'
+openstackdocs_pdf_link = True
+openstackdocs_bug_project = 'python-congressclient'
+openstackdocs_bug_tag = ''
 
 # sphinxcontrib.apidoc options
 apidoc_module_dir = '../../congressclient'
@@ -37,7 +38,6 @@ apidoc_excluded_paths = ['tests/*']
 
 apidoc_separate_modules = True
 
-html_last_updated_fmt = '%Y-%m-%d %H:%M'
 
 # autodoc generation is a bit aggressive and a nuisance when doing heavy
 # text edit cycles.
@@ -61,7 +61,7 @@ add_function_parentheses = True
 add_module_names = True
 
 # The name of the Pygments (syntax highlighting) style to use.
-pygments_style = 'sphinx'
+pygments_style = 'native'
 
 # A list of glob-style patterns that should be excluded when looking for
 # source files. They are matched against the source file names relative to the

lower-constraints.txt

@@ -26,7 +26,6 @@ msgpack-python==0.4.0
 msgpack==0.5.6
 netaddr==0.7.19
 netifaces==0.10.6
-openstackdocstheme==1.32.1
 oslo.config==5.2.0
 oslo.context==2.20.0
 oslo.i18n==3.15.3
@@ -50,8 +49,6 @@ requests==2.18.4
 rfc3986==1.1.0
 six==1.10.0
 snowballstemmer==1.2.1
-Sphinx==1.8.0
-sphinxcontrib-websupport==1.0.1
 stevedore==1.28.0
 stestr==2.0.0
 testtools==2.2.0

releasenotes/source/conf.py

@@ -52,13 +52,14 @@ source_suffix = '.rst'
 master_doc = 'index'
 
 # General information about the project.
-project = u'congress_tempest_plugin Release Notes'
+project = u'python-congressclient Release Notes'
 copyright = u'2017, OpenStack Developers'
 
 # openstackdocstheme options
-repository_name = 'openstack/congress-tempest-plugin'
-bug_project = 'congress'
-bug_tag = ''
+openstackdocs_repo_name = 'openstack/congress-tempest-plugin'
+openstackdocs_bug_project = 'congress'
+openstackdocs_bug_tag = ''
+openstackdocs_auto_name = False
 
 # The version info for the project you're documenting, acts as replacement for
 # |version| and |release|, also used in various other places throughout the
@@ -100,7 +101,7 @@ exclude_patterns = []
 # show_authors = False
 
 # The name of the Pygments (syntax highlighting) style to use.
-pygments_style = 'sphinx'
+pygments_style = 'native'
 
 # A list of ignored prefixes for module index sorting.
 # modindex_common_prefix = []