Switch to newer openstackdocstheme version

Switch to openstackdocstheme 2.2.1 version. Using
this version 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: I9d8b24733842e364fc6ef05b9e9adebae2a66ee5

doc/source/conf.py

@@ -28,7 +28,7 @@ extensions = [
 ]
 
 # Feed configuration for yasfb
-feed_base_url = 'http://specs.openstack.org/openstack/zaqar-specs'
+feed_base_url = 'https://specs.openstack.org/openstack/zaqar-specs'
 feed_author = 'OpenStack Zaqar Team'
 
 exclude_patterns = [
@@ -66,7 +66,13 @@ add_function_parentheses = True
 add_module_names = True
 
 # The name of the Pygments (syntax highlighting) style to use.
-pygments_style = 'sphinx'
+pygments_style = 'native'
+
+# openstackdocstheme options
+openstackdocs_repo_name = 'openstack/zaqar-specs'
+openstackdocs_auto_name = False
+openstackdocs_bug_project = 'zaqar'
+openstackdocs_bug_tag = ''
 
 # -- Options for HTML output --------------------------------------------------
 

requirements.txt

@@ -1,6 +1,6 @@
 pbr>=0.6,<1.0
-openstackdocstheme
-sphinx!=1.6.6,!=1.6.7,!=2.1.0,>=1.6.2;python_version>='3.4' # BSD
+openstackdocstheme>=2.2.1 # Apache-2.0
+sphinx>=2.0.0,!=2.1.0 # BSD
 yasfb>=0.8.0
 testrepository>=0.0.18
 testtools>=0.9.34