Merge "Leverage ignore_basepython_conflict to get the right python version"

tox.ini

@@ -1,7 +1,8 @@
 [tox]
-minversion = 1.6
+minversion = 3.1.0
 skipsdist = True
 envlist = validate,py27,pep8,pip-install
+ignore_basepython_conflict=true
 
 [testenv]
 basepython = python3
@@ -58,7 +59,6 @@ deps =
     hacking>=1.0.0
     bashate>=0.5.1
 whitelist_externals = bash
-basepython = python3
 commands =
     flake8
     bash -c "find {toxinidir}/tools      \
@@ -86,17 +86,7 @@ deps = .
 install_command = pip install {opts} {packages}
 commands = python {toxinidir}/tools/check-install.py
 
-[testenv:py34]
-basepython = python3.4
-
-[testenv:py35]
-basepython = python3.5
-
-[testenv:py36]
-basepython = python3.6
-
 [testenv:requirements-check]
-basepython = python3
 deps = -r{toxinidir}/requirements.txt
 commands =
   {toxinidir}/playbooks/files/project-requirements-change.py --local {posargs}