Follow the new PTI for document build

For compliance with the Project Testing Interface as described in:

https://governance.openstack.org/tc/reference/project-testing-interface.html

For more detials information, please refer to:

http://lists.openstack.org/pipermail/openstack-dev/2017-December/125710.html

Change-Id: I39b9806013a0912b27c0523dfc2b713b3105bdf1

setup.cfg

@@ -83,15 +83,6 @@ oslo.config.opts =
 [wheel]
 universal = 1
 
-[build_sphinx]
-warning-is-error = 1
-all-files = 1
-source-dir = doc/source
-build-dir = doc/build
-
-[upload_sphinx]
-upload-dir = doc/build/html
-
 [compile_catalog]
 directory = oslo_messaging/locale
 domain = oslo_messaging

tox.ini

@@ -28,8 +28,8 @@ commands = {posargs}
 
 [testenv:docs]
 basepython = python2.7
-commands = python setup.py build_sphinx
 deps = -r{toxinidir}/doc/requirements.txt
+commands = sphinx-build -W -b html doc/source doc/build/html
 
 [testenv:py27-func-rabbit]
 setenv =