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.

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: I8edb19b7855f8ed108566b13ce0a277a2073e3a2

doc/requirements.txt

@@ -1,3 +1,3 @@
-sphinx!=1.6.6,!=1.6.7,!=2.1.0,>=1.6.2;python_version>='3.4' # BSD
-openstackdocstheme>=1.20.0 # Apache-2.0
-reno>=2.5.0 # Apache-2.0
+sphinx>=2.0.0,!=2.1.0 # BSD
+openstackdocstheme>=2.2.1 # Apache-2.0
+reno>=3.1.0 # Apache-2.0

doc/source/conf.py

@@ -46,9 +46,9 @@ master_doc = 'index'
 copyright = u'2016, OpenStack'
 
 # openstackdocstheme options
-repository_name = 'openstack/python-freezerclient'
-bug_project = 'freezer'
-bug_tag = 'python-freezerclient'
+openstackdocs_repo_name = 'openstack/python-freezerclient'
+openstackdocs_bug_project = 'freezer'
+openstackdocs_bug_tag = 'python-freezerclient'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
@@ -80,7 +80,7 @@ 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 = []

lower-constraints.txt

@@ -19,7 +19,6 @@ MarkupSafe==1.0
 monotonic==0.6
 netaddr==0.7.18
 netifaces==0.10.4
-openstackdocstheme==1.20.0
 oslo.i18n==3.15.3
 oslo.serialization==2.25.0
 oslo.utils==3.33.0
@@ -33,12 +32,9 @@ python-mimeparse==1.6.0
 python-subunit==1.0.0
 pytz==2013.6
 PyYAML==3.12
-reno==2.5.0
 requests==2.14.2
 setuptools==21.0.0
 snowballstemmer==1.2.1
-Sphinx==1.6.5
-sphinxcontrib-websupport==1.0.1
 stevedore==1.20.0
 stestr==2.0.0
 testtools==2.2.0

releasenotes/source/conf.py

@@ -44,9 +44,9 @@ master_doc = 'index'
 # General information about the project.
 copyright = u'2016, Freezer developers'
 
-repository_name = 'openstack/python-freezerclient'
-bug_project = 'freezer'
-bug_tag = 'python-freezerclient'
+openstackdocs_repo_name = 'openstack/python-freezerclient'
+openstackdocs_bug_project = 'freezer'
+openstackdocs_bug_tag = 'python-freezerclient'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
@@ -78,7 +78,7 @@ 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 = []