Py3 compatibility as proposed in issue #17

I've done 3 verifications with this branch:
 1. run it in app
 1. call `python2.7 utils.py`
 1. call `2to3` on the module's root dir

So far my app sends messages to the service. That would make the other complaints `2to3` has purely optional for me. Also the altered file loaded with a current py2 interpreter which should be a sufficient integration test for this particular change.