chore: Remove django > 1.8 from tox envs

tox.ini

@@ -1,30 +1,28 @@
 [tox]
 envlist =
     flake8,isort
-    {py27}-{django14},
-    {py27,py34}-{django15,django16,django17,django18,django19}
+    {py27,py3}-{django18,django19}
 skipsdist = True
 
 [testenv]
+basepython =
+    py3: python3
+    py27: python2
 setenv =
     PYTHONPATH = {toxinidir}:{toxinidir}
 commands =
     coverage run -p --source=nopassword runtests.py
 deps =
     -r{toxinidir}/requirements.txt
-    django14: Django>=1.4,<1.5
-    django15: Django>=1.5,<1.6
-    django16: Django>=1.6,<1.7
-    django17: Django>=1.7,<1.8
     django18: Django>=1.8,<1.9
     django19: Django>=1.9,<1.10
 
 [testenv:flake8]
-basepython = python3.4
+basepython = python3
 deps = flake8
 commands = flake8
 
 [testenv:isort]
-basepython = python3.4
+basepython = python3
 deps = isort
 commands = isort -c -rc nopassword tests