Update new documentation PTI jobs

For compliance with the Project Testing Interface as described in [1].
For more detailed information, please refer to [2].

[1] https://governance.openstack.org/tc/reference/project-testing-interface.html
[2] http://lists.openstack.org/pipermail/openstack-dev/2017-December/125710.html

Change-Id: Ia6b5bc846ecf8550bce8506046a52e1f67ef28de

doc/requirements.txt

@@ -0,0 +1,4 @@
+sphinx>=1.6.2 # BSD
+oslosphinx>=4.7.0 # Apache-2.0
+openstackdocstheme>=1.17.0 # Apache-2.0
+reno>=2.5.0 # Apache-2.0

test-requirements.txt

@@ -8,9 +8,6 @@ fixtures>=3.0.0 # Apache-2.0/BSD
 mock>=2.0.0 # BSD
 flake8-import-order==0.12 # LGPLv3
 requests-mock>=1.2.0 # Apache-2.0
-sphinx!=1.6.6,!=1.6.7,>=1.6.2 # BSD
-oslosphinx>=4.7.0 # Apache-2.0
-openstackdocstheme>=1.18.1 # Apache-2.0
 oslo.concurrency>=3.26.0 # Apache-2.0
 oslotest>=3.2.0 # Apache-2.0
 stestr>=1.0.0 # Apache-2.0
@@ -18,5 +15,4 @@ testresources>=2.0.0 # Apache-2.0/BSD
 testtools>=2.2.0 # MIT
 testscenarios>=0.4 # Apache-2.0/BSD
 WebOb>=1.7.1 # MIT
-reno>=2.5.0 # Apache-2.0
 tempest>=17.1.0 # Apache-2.0

tox.ini

@@ -21,6 +21,10 @@ commands =
 
 [testenv:releasenotes]
 basepython = python3
+deps =
+  -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
+  -r{toxinidir}/requirements.txt
+  -r{toxinidir}/doc/requirements.txt
 commands = sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
 
 [testenv:pep8]
@@ -48,7 +52,11 @@ commands = {posargs}
 
 [testenv:docs]
 basepython = python3
-commands = python setup.py build_sphinx
+deps =
+  -c{env:UPPER_CONSTRAINTS_FILE:https://git.openstack.org/cgit/openstack/requirements/plain/upper-constraints.txt}
+  -r{toxinidir}/requirements.txt
+  -r{toxinidir}/doc/requirements.txt
+commands = sphinx-build -b html doc/source doc/build/html
 
 [flake8]
 # E125 continuation line does not distinguish itself from next logical line