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.

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: I3532fe039e754c3518a25b72094bf421d1f1c299

doc/source/conf.py

@@ -50,7 +50,7 @@ add_function_parentheses = True
 add_module_names = True
 
 # The name of the Pygments (syntax highlighting) style to use.
-pygments_style = 'sphinx'
+pygments_style = 'native'
 
 # -- Options for HTML output --------------------------------------------------
 
@@ -78,6 +78,6 @@ latex_documents = [
 # intersphinx_mapping = {'http://docs.python.org/': None}
 
 # openstackdocstheme options
-repository_name = 'openstack/tripleo-common'
+openstackdocs_repo_name = 'openstack/tripleo-common'
-bug_project = 'tripleo'
+openstackdocs_bug_project = 'tripleo'
-bug_tag = 'documentation'
+openstackdocs_bug_tag = 'documentation'

lower-constraints.txt

@@ -41,7 +41,7 @@ msgpack-python==0.4.0
 munch==2.1.0
 netaddr==0.7.18
 netifaces==0.10.4
-openstackdocstheme==1.31.2
+openstackdocstheme==2.2.1
 openstacksdk==0.11.2
 os-client-config==1.28.0
 os-service-types==1.2.0
@@ -85,7 +85,7 @@ python-swiftclient==3.2.0
 python-zaqarclient==1.0.0
 pytz==2013.6
 PyYAML==3.12
-reno==2.5.0
+reno==3.1.0
 requests-mock==1.2.0
 requests==2.18.0
 requestsexceptions==1.2.0
@@ -94,7 +94,7 @@ simplejson==3.5.1
 six==1.10.0
 smmap==0.9.0
 snowballstemmer==1.2.1
-Sphinx==1.8.0
+Sphinx==2.0.0
 sphinxcontrib-websupport==1.0.1
 stestr==2.0.0
 stevedore==1.20.0

releasenotes/source/conf.py

@@ -87,7 +87,7 @@ 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 = []
@@ -257,6 +257,6 @@ texinfo_documents = [
 locale_dirs = ['locale/']
 
 # openstackdocstheme options
-repository_name = 'openstack/tripleo-common'
+openstackdocs_repo_name = 'openstack/tripleo-common'
-bug_project = 'tripleo'
+openstackdocs_bug_project = 'tripleo'
-bug_tag = 'documentation'
+openstackdocs_bug_tag = 'documentation'

test-requirements.txt

@@ -2,17 +2,17 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 
-openstackdocstheme>=1.31.2 # Apache-2.0
+openstackdocstheme>=2.2.1 # Apache-2.0
 
 coverage!=4.4,>=4.0 # Apache-2.0
 docutils>=0.11 # OSI-Approved Open Source, Public Domain
 python-subunit>=1.0.0 # Apache-2.0/BSD
-sphinx>=1.8.0,!=2.1.0 # BSD
+sphinx>=2.0.0,!=2.1.0 # BSD
 oslotest>=3.2.0 # Apache-2.0
 stestr>=2.0.0 # Apache-2.0
 testscenarios>=0.4 # Apache-2.0/BSD
 testtools>=2.2.0 # MIT
 PyYAML>=3.12 # MIT
-reno>=2.5.0 # Apache-2.0
+reno>=3.1.0 # Apache-2.0
 urllib3>=1.21.1  # MIT
 requests-mock>=1.2.0 # Apache-2.0