travis-ci: Add support for running test with Travis CI
travis-ci: Add support for running test with Travis CI

This configuration file tells Travis CI how to run our
unittests with tox in a number of different environments.
This is useful for allowing us to show our build status
on the project page and ensure community-contributed
changes do not break the build.

digidotcom/python-devicecloud,digidotcom/python-devicecloud,ctrlaltdel/python-devicecloud,brucetsao/python-devicecloud,ctrlaltdel/python-devicecloud,michaelcho/python-devicecloud,michaelcho/python-devicecloud,brucetsao/python-devicecloud