Update .travis.yml

Add code to compile .po files before beginning tests

.travis.yml

@@ -9,6 +9,7 @@ env:
 install: "pip install -r requirements.txt"
 script:
 - flake8
+- python manage.py compilemessages
 - python manage.py test -v 3
 # - coverage run --source='.' manage.py test dynamicweb -v 3
 # - coverage report