Add Travis CI

#### [Travis CI](https://travis-ci.com)

> All affected infrastructure has been updated, API keys revoked. As per https://github.com/blog/1818-security-heartbleed-vulnerability you'd be well advised to also revoke and delete any OAuth token and re-authenticate with Travis CI.

Official Source: http://status.travis-ci.com/incidents/jb8sz5t5r1td