Fix bandit and sphinx requirements for stable branches

This is a combination of 2 commits.

1st commit:
Update Sphinx requirement
Sphinx 2.0 no longer works on python 2.7, so we need to start capping
it there as well.

2nd commit:
Fix bandit runs with 1.6.0
The -x option for bandit changed in 1.6.0 and now
supports glob patterns so use that to correctly
exclude test code from bandit scans.

Change-Id: I588d3fb02ef61623affd82a43a54585aba0cb5f9

doc/requirements.txt

@@ -2,7 +2,8 @@
 # of appearance. Changing the order has an impact on the overall integration
 # process, which may cause wedges in the gate later.
 openstackdocstheme>=1.20.0 # Apache-2.0
-sphinx>=1.6.5,!=1.6.6,!=1.6.7 # BSD
+sphinx>=1.6.5,!=1.6.6,!=1.6.7,<2.0.0;python_version=='2.7' # BSD
+sphinx>=1.6.5,!=1.6.6,!=1.6.7;python_version>='3.4' # BSD
 sphinxcontrib-pecanwsme>=0.8.0 # Apache-2.0
 reno>=2.7.0 # Apache-2.0
 sphinxcontrib-apidoc>=0.2.0  # BSD

requirements.txt

@@ -45,5 +45,7 @@ stevedore>=1.28.0 # Apache-2.0
 taskflow>=3.1.0 # Apache-2.0
 WebOb>=1.7.4 # MIT
 WSME>=0.9.2 # MIT
-networkx>=1.11 # BSD
+# NOTE(fdegir): NetworkX 2.3 dropped support for Python 2
+networkx>=1.11,<2.3;python_version<'3.0'  # BSD
+networkx>=1.11;python_version>='3.4' # BSD
 microversion_parse>=0.2.1 # Apache-2.0

test-requirements.txt

@@ -13,4 +13,4 @@ testscenarios>=0.5.0 # Apache-2.0/BSD
 testtools>=2.3.0 # MIT
 stestr>=2.0.0 # Apache-2.0
 os-api-ref>=1.4.0 # Apache-2.0
-bandit>=1.1.0 # Apache-2.0
+bandit>=1.6.0 # Apache-2.0

tox.ini

@@ -22,7 +22,7 @@ basepython = python3
 commands =
     doc8 doc/source/ CONTRIBUTING.rst HACKING.rst README.rst
     flake8
-    bandit -r watcher -x tests -n5 -ll -s B320
+    bandit -r watcher -x watcher/tests/* -n5 -ll -s B320
 
 [testenv:venv]
 basepython = python3
@@ -98,7 +98,7 @@ commands = sphinx-build -a -W -E -d releasenotes/build/doctrees -b html releasen
 [testenv:bandit]
 basepython = python3
 deps = -r{toxinidir}/test-requirements.txt
-commands = bandit -r watcher -x tests -n5 -ll -s B320
+commands = bandit -r watcher -x watcher/tests/* -n5 -ll -s B320
 
 [testenv:lower-constraints]
 basepython = python3