Add Python 3.3 and 3.4 to Travis CI

.travis.yml

@@ -3,6 +3,8 @@ sudo: false
 language: python
 python:
   - 2.7
+  - 3.3
+  - 3.4
   - 3.5
 before_install:
   ## courtesy of http://conda.pydata.org/docs/travis.html