Removing travis check for python 3.3 since tox do not support it and most libraries already removed support for the old python 3.3.

.travis.yml

@@ -9,8 +9,6 @@ matrix:
       env: TOXENV=py3flake8
     - python: 2.7
       env: TOXENV=py27
-    - python: 3.3
-      env: TOXENV=py33
     - python: 3.4
       env: TOXENV=py34
     - python: 3.5

tox.ini

@@ -1,6 +1,6 @@
 [tox]
 minversion = 1.7.2
-envlist = flake8, py3flake8, py27, py33, py34, py35, py36, pypy, pypy3
+envlist = flake8, py3flake8, py27, py34, py35, py36, pypy, pypy3
 skip_missing_interpreters = true
 
 [testenv]