Add doc/requirements

We need to specify doc requirements in doc/requirements.txt
to avoid problems with the pip resolver for the release team.
Removed specific doc requirements from test-requirements.txt

Change-Id: I2d3a6e6bb0db372565458ea5eed4d84efdef37d2

doc/requirements.txt

@@ -0,0 +1,6 @@
+reno>=3.1.0 # Apache-2.0
+sphinx>=2.0.0,!=2.1.0 # BSD
+sphinxcontrib-apidoc>=0.2.0  # BSD
+sphinxcontrib-svg2pdfconverter>=0.1.0 # BSD
+openstackdocstheme>=2.2.1 # Apache-2.0
+

test-requirements.txt

@@ -7,9 +7,6 @@ coverage!=4.4,>=4.0 # Apache-2.0
 fixtures>=3.0.0 # Apache-2.0/BSD
 flake8-import-order==0.12 # LGPLv3
 python-subunit>=1.0.0 # Apache-2.0/BSD
-sphinx>=2.0.0,!=2.1.0 # BSD
-sphinxcontrib-svg2pdfconverter>=0.1.0 # BSD
-openstackdocstheme>=2.2.1 # Apache-2.0
 oslo.concurrency>=3.26.0 # Apache-2.0
 stestr>=1.0.0 # Apache-2.0
 testresources>=2.0.0 # Apache-2.0/BSD
@@ -18,5 +15,4 @@ testscenarios>=0.4 # Apache-2.0/BSD
 WebOb>=1.8.2 # MIT
 WebTest>=2.0.27 # MIT
 oslotest>=3.2.0 # Apache-2.0
-reno>=3.1.0 # Apache-2.0
 tempest>=17.1.0 # Apache-2.0

tox.ini

@@ -46,6 +46,7 @@ commands =
   stestr run {posargs}
 
 [testenv:releasenotes]
+deps = {[testenv:docs]deps}
 commands = sphinx-build -a -E -W -d releasenotes/build/doctrees -b html releasenotes/source releasenotes/build/html
 
 [testenv:pep8]
@@ -69,12 +70,14 @@ commands =
 commands = {posargs}
 
 [testenv:docs]
+deps = -c{env:TOX_CONSTRAINTS_FILE:https://releases.openstack.org/constraints/upper/master}
+       -r{toxinidir}/doc/requirements.txt
 commands =
   sphinx-build -W -b html doc/source doc/build/html
 
 [testenv:pdf-docs]
 envdir = {toxworkdir}/docs
-# deps = {[testenv:docs]deps}
+deps = {[testenv:docs]deps}
 whitelist_externals =
   make
 commands =