Switch to newer openstackdocstheme and reno versions

Switch to openstackdocstheme 2.2.0 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.

Change-Id: I42b7a7d44fc50218f99f6106324945864b46d74f

doc/requirements.txt

@@ -1,4 +1,4 @@
-openstackdocstheme>=1.20.0 # Apache-2.0
+openstackdocstheme>=2.2.0 # Apache-2.0
-reno>=1.8.0 # Apache-2.0
+reno>=3.1.0 # Apache-2.0
-sphinx!=1.6.6,!=1.6.7,!=2.1.0,>=1.6.2 # BSD
+sphinx>=2.0.0,!=2.1.0 # BSD
 sphinx-argparse>=0.2.2 # MIT

doc/source/conf.py

@@ -27,9 +27,8 @@ extensions = [
 html_theme = 'openstackdocs'
 
 # openstackdocstheme options
-repository_name = 'openstack/python-tempestconf'
+openstackdocs_repo_name = 'openstack/python-tempestconf'
-bug_project = '912'
+openstackdocs_use_storyboard = True
-bug_tag = 'doc'
 
 # autodoc generation is a bit aggressive and a nuisance when doing heavy
 # text edit cycles.

releasenotes/source/conf.py

@@ -43,9 +43,8 @@ extensions = [
 ]
 
 # openstackdocstheme options
-repository_name = 'openstack/python-tempestconf'
+openstackdocs_repo_name = 'openstack/python-tempestconf'
-bug_project = '912'
+openstackdocs_use_storyboard = True
-bug_tag = 'releasenotes'
 
 # Add any paths that contain templates here, relative to this directory.
 templates_path = ['_templates']