Merge "fix tox python3 overrides"

tox.ini

@@ -8,6 +8,7 @@ usedevelop = False
 install_command = pip install {opts} {packages}
 
 [testenv:bashate]
+basepython = python3
 # if you want to test out some changes you have made to bashate
 # against devstack, just set BASHATE_INSTALL_PATH=/path/... to your
 # modified bashate tree
@@ -34,6 +35,7 @@ commands = bash -c "find {toxinidir}             \
          -print0 | xargs -0 bashate -v -iE006 -eE005,E042"
 
 [testenv:docs]
+basepython = python3
 deps = -r{toxinidir}/doc/requirements.txt
 whitelist_externals = bash
 setenv =
@@ -42,5 +44,6 @@ commands =
   python setup.py build_sphinx
 
 [testenv:venv]
+basepython = python3
 deps = -r{toxinidir}/doc/requirements.txt
 commands = {posargs}