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

Change-Id: Ib988f55336b2531f66b899e6426097317681757e

doc/requirements.txt

@@ -0,0 +1,3 @@
+sphinx>=1.6.2 # BSD
+oslosphinx>=4.7.0 # Apache-2.0
+reno>=2.5.0 # Apache-2.0

setup.cfg

@@ -33,14 +33,6 @@ openstack.valence.v1 =
     valence_podmanager_delete = valenceclient.osc.v1.podmanager:DeletePodManagers
     valence_podmanager_show = valenceclient.osc.v1.podmanager:ShowPodManager
 
-[build_sphinx]
-source-dir = doc/source
-build-dir = doc/build
-all_files = 1
-
-[upload_sphinx]
-upload-dir = doc/build/html
-
 [compile_catalog]
 directory = valenceclient/locale
 domain = valenceclient

test-requirements.txt

@@ -6,8 +6,6 @@ hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
 
 coverage!=4.4,>=4.0 # Apache-2.0
 python-subunit>=1.0.0 # Apache-2.0/BSD
-sphinx>=1.6.2 # BSD
-oslosphinx>=4.7.0 # Apache-2.0
 oslotest>=3.2.0 # Apache-2.0
 testrepository>=0.0.18 # Apache-2.0/BSD
 testscenarios>=0.4 # Apache-2.0/BSD
@@ -16,6 +14,3 @@ oslo.utils>=3.33.0 # Apache-2.0
 oslo.i18n>=3.15.3 # Apache-2.0
 oslo.serialization!=2.19.1,>=2.18.0 # Apache-2.0
 requests-mock>=1.1.0 # Apache-2.0
-
-# releasenotes
-reno>=2.5.0 # Apache-2.0

tox.ini

@@ -22,9 +22,11 @@ commands = {posargs}
 commands = python setup.py test --coverage --testr-args='{posargs}'
 
 [testenv:docs]
-commands = python setup.py build_sphinx
+deps = -r{toxinidir}/doc/requirements.txt
+commands = sphinx-build -W -b html doc/source doc/build/html
 
 [testenv:releasenotes]
+deps = -r{toxinidir}/doc/requirements.txt
 commands =
   sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html