Switch to newer openstackdocstheme version3.1.0

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.

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: I6c6775f75235dab2b9ed7820bfc5102bf5b04965

1 files changed, 4 insertions, 4 deletions

diff --git a/doc/source/conf.py b/doc/source/conf.py
index 03b99e2..2167d9f 100644
--- a/doc/source/conf.py
+++ b/doc/source/conf.py
@@ -81,7 +81,7 @@ exclude_patterns = ['_build']
 #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 = []
@@ -241,6 +241,6 @@ texinfo_documents = [
 #texinfo_no_detailmenu = False
 
 # -- Options for openstackdocstheme -------------------------------------------
-repository_name = 'openstack/pycadf'
-bug_project = 'pycadf'
-bug_tag = ''
+openstackdocs_repo_name = 'openstack/pycadf'
+openstackdocs_bug_project = 'pycadf'
+openstackdocs_bug_tag = ''