Cleanup py27 support and docs

This repo is now testing docs only with Python 3, so let's make
a few cleanups:
- Remove obsolete sections from setup.cfg
- Switch to using sphinx-build
- Cleanup doc/source/conf.py to remove now obsolete content.
- Use newer openstackdocstheme version
- Remove install_command from tox.ini, the default is fine

Change-Id: Iffd00261e6a15e2dd7c98e96bbcc9db3e86c0c65

doc/requirements.txt

@@ -3,4 +3,4 @@
 # process, which may cause wedges in the gate later.
 sphinx!=1.6.6,!=1.6.7,!=2.1.0,>=1.6.2
 sphinxcontrib-blockdiag>=1.1.0
-openstackdocstheme>=1.18.1 # Apache-2.0
+openstackdocstheme>=1.31.2 # Apache-2.0

doc/source/conf.py

@@ -63,11 +63,6 @@ html_theme = 'openstackdocs'
 # so a file named "default.css" will overwrite the builtin "default.css".
 html_static_path = ['_static']
 
-# If not '', a 'Last updated on:' timestamp is inserted at every page bottom,
-# using the given strftime format.
-# html_last_updated_fmt = '%b %d, %Y'
-html_last_updated_fmt = '%Y-%m-%d %H:%M'
-
 # The theme to use for HTML and HTML Help pages.  Major themes that come with
 # Sphinx are currently 'default' and 'sphinxdoc'.
 # html_theme_path = ["."]

setup.cfg

@@ -10,12 +10,3 @@ classifier =
     Intended Audience :: Developers
     License :: OSI Approved :: Apache Software License
     Operating System :: POSIX :: Linux
-
-[build_sphinx]
-all_files = 1
-build-dir = doc/build
-source-dir = doc/source
-warning-is-error = True
-
-[wheel]
-universal = 1

tox.ini

@@ -6,7 +6,6 @@ ignore_basepython_conflict = True
 
 [testenv]
 basepython = python3
-install_command = pip install -U {opts} {packages}
 setenv = VIRTUAL_ENV={envdir}
 deps = -c{env:UPPER_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
 passenv = *_proxy *_PROXY
@@ -17,7 +16,7 @@ commands = {posargs}
 [testenv:docs]
 deps = -r{toxinidir}/doc/requirements.txt
 commands =
-  bash -c "rm -rf doc/build"
-  python setup.py build_sphinx
+  rm -rf doc/build
+  sphinx-build -W -b html doc/source doc/source/html
 whitelist_externals =
-  bash
+  rm