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

Remove the '[build_sphinx]' as described in:
http://lists.openstack.org/pipermail/openstack-dev/2018-March/128594.html

Update openstackdocstheme, sphinx and reno versions at the same time.

Change-Id: I8454b83f6ef200f8c5d34bee8568831b1e8fa15e

doc/requirements.txt

@@ -0,0 +1,7 @@
+# The order of packages is significant, because pip processes them in the order
+# of appearance. Changing the order has an impact on the overall integration
+# process, which may cause wedges in the gate later.
+
+openstackdocstheme>=1.18.1 # Apache-2.0
+sphinx!=1.6.6,!=1.6.7,>=1.6.2 # BSD
+reno>=2.5.0  # Apache2

setup.cfg

@@ -147,12 +147,6 @@ keystoneauth1.plugin =
 cliff.formatter.list =
     df-to-csv = cloudkittyclient.format:DataframeToCsvFormatter
 
-[build_sphinx]
-source-dir = doc/source
-build-dir = doc/build
-all_files = 1
-warning-is-error = 1
-
 [upload_sphinx]
 upload-dir = doc/build/html
 

test-requirements.txt

@@ -6,10 +6,7 @@ hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
 
 coverage!=4.4,>=4.0 # Apache-2.0
 python-subunit>=0.0.18 # Apache-2.0/BSD
-sphinx>=1.6.2 # BSD
-openstackdocstheme>=1.11.0 # Apache-2.0
 oslotest>=1.10.0 # Apache-2.0
-reno>=1.8.0  # Apache2
 stestr>=2.0 # Apache-2.0
 mock>=2.0 # BSD
 python-openstackclient>=3.14 # Apache-2.0

tox.ini

@@ -30,7 +30,8 @@ commands = {posargs}
 
 [testenv:docs]
 basepython = python3
-commands = python setup.py build_sphinx
+deps = -r{toxinidir}/doc/requirements.txt
+commands = sphinx-build -W -b html doc/source doc/build/html
 
 [flake8]
 # E123, E125 skipped as they are invalid PEP-8.
@@ -45,4 +46,5 @@ import_exceptions = cloudkittyclient.i18n
 
 [testenv:releasenotes]
 basepython = python3
+deps = -r{toxinidir}/doc/requirements.txt
 commands = sphinx-build -a -E -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html