Add other python versions for travis

Author: bambocher

.travis.yml

@@ -2,10 +2,15 @@ language: python
 python:
   - "2.6"
   - "2.7"
+  - "3.0"
+  - "3.1"
   - "3.2"
   - "3.3"
   - "3.4"
   - "3.5"
+  - "3.5-dev"
+  - "nightly"
+  - "pypy"
 before_install:
   - sudo apt-get update -qq
   - sudo apt-get install -qq build-essential swig