Add config file for tox.

Author: ahawker

Diff for: tox.ini

@@ -0,0 +1,16 @@
+[tox]
+envlist = py34, py35, py36, lint
+
+[testenv]
+commands = make test
+whitelist_externals = make
+usedevelop = true
+
+[testenv:lint]
+commands = make lint
+
+[travis]
+python =
+    3.4: py34
+    3.5: py35
+    3.6: py36