Enable Travis CI

I've added a basic Travis CI configuration file for Python and a simple test (that always passes) to ensure Travis works.

For now, I configured Travis to simply install the toopher package, but in the future we may want to move dependencies into a `requirements.txt` file for Pip. I've commented out that line in the `.travis.yml` for reference.

For more, see the [Travis CI Getting Started Guide](http://about.travis-ci.org/docs/user/getting-started/).