Add Travis CI to do automated testing on all PRs
Add Travis CI to do automated testing on all PRs

[Travis CI](https://travis-ci.org) is a framework for running tests which is free for open source projects like this one.  The owner of the this repo would need to go to https://travis-ci.org/profile and flip the repository switch __on__ to enable free automated testing of each pull request.  [Flake8](http://flake8.pycqa.org) is a linter that can help to find Python syntax errors, undefined names, and other code quality issues.  Other linters could be run for the other languages.
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