Merge pull request #203 from collective/gforcada-patch-1

Test with pypy and pypy3

.travis.yml

@@ -4,6 +4,8 @@ python:
   - "2.7"
   - "3.3"
   - "3.4"
+  - "pypy"
+  - "pypy3"
 install:
   - pip install tox
 script: