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.

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.

See also
http://lists.openstack.org/pipermail/openstack-discuss/2020-May/014971.html

Fix gitpython requirement to unbreak requirements-check job.

Change-Id: I59215a9cf2efbe4125c33766a791cbc3c6cdf068

doc/requirements.txt

@@ -1,5 +1,5 @@
-sphinx!=1.6.6,!=1.6.7,>=1.6.2 # BSD
-openstackdocstheme>=1.18.1 # Apache-2.0
+sphinx>=2.0.0,!=2.1.0 # BSD
+openstackdocstheme>=2.2.1 # Apache-2.0
 sphinxcontrib-pecanwsme>=0.8.0 # Apache-2.0
 sphinxcontrib-httpdomain>=1.3.0 # BSD
-reno>=2.5.0 # Apache-2.0
+reno>=3.1.0 # Apache-2.0

doc/source/conf.py

@@ -47,7 +47,7 @@ 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 --------------------------------------------------
 
@@ -60,12 +60,10 @@ pygments_style = 'sphinx'
 html_theme = 'openstackdocs'
 
 # openstackdocstheme options
-repository_name = 'openstack/murano-agent'
-bug_project = 'murano'
-bug_tag = ''
-
-# Must set this variable to include year, month, day, hours, and minutes.
-html_last_updated_fmt = '%Y-%m-%d %H:%M'
+openstackdocs_repo_name = 'openstack/murano-agent'
+openstackdocs_auto_name = False
+openstackdocs_bug_project = 'murano'
+openstackdocs_bug_tag = ''
 
 # Output file base name for HTML help builder.
 htmlhelp_basename = '%sdoc' % project

lower-constraints.txt

@@ -37,7 +37,6 @@ mox3==0.25.0
 msgpack==0.5.6
 netaddr==0.7.19
 netifaces==0.10.6
-openstackdocstheme==1.20.0
 os-client-config==1.29.0
 oslo.concurrency==3.26.0
 oslo.config==5.2.0
@@ -62,7 +61,6 @@ python-mimeparse==1.6.0
 python-subunit==1.2.0
 pytz==2018.3
 PyYAML==3.12
-reno==2.7.0
 repoze.lru==0.7
 requests==2.18.4
 requestsexceptions==1.4.0
@@ -71,8 +69,6 @@ Routes==2.4.1
 semantic-version==2.6.0
 smmap2==2.0.3
 snowballstemmer==1.2.1
-Sphinx==1.6.5
-sphinxcontrib-websupport==1.0.1
 stevedore==1.28.0
 stestr==2.0.0
 testtools==2.3.0

releasenotes/source/conf.py

@@ -95,7 +95,7 @@ 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 = []
@@ -111,12 +111,10 @@ pygments_style = 'sphinx'
 html_theme = 'openstackdocs'
 
 # openstackdocstheme options
-repository_name = 'openstack/murano-agent'
-bug_project = 'murano'
-bug_tag = ''
-
-# Must set this variable to include year, month, day, hours, and minutes.
-html_last_updated_fmt = '%Y-%m-%d %H:%M'
+openstackdocs_repo_name = 'openstack/murano-agent'
+openstackdocs_auto_name = False
+openstackdocs_bug_project = 'murano'
+openstackdocs_bug_tag = ''
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the

requirements.txt

@@ -4,7 +4,7 @@
 pbr>=3.1.1 # Apache-2.0
 anyjson>=0.3.3 # BSD
 eventlet>=0.20.0,!=0.20.1,!=0.21.0 # MIT
-GitPython>=3.0.5;python_version>='3.0'  # BSD License (3 clause)
+GitPython>=3.0.5 # BSD License (3 clause)
 kombu>=4.1.0 # BSD
 oslo.config>=5.2.0 # Apache-2.0
 oslo.log>=3.37.0 # Apache-2.0