Re: Add a travis job for testing PR stability (#3975)

Testing in **Firefox**
Files changed:
 * /home/travis/build/w3c/web-platform-tests/.travis.yml
 * /home/travis/build/w3c/web-platform-tests/check_stability.py
 * /home/travis/build/w3c/web-platform-tests/ci_lint.sh
 * /home/travis/build/w3c/web-platform-tests/ci_stability.sh

All results were stable

## All results ##

| Test | Subtest | Results |
|------|---------|---------|

View on GitHub: https://github.com/w3c/web-platform-tests/pull/3975#issuecomment-255101072

Received on Thursday, 20 October 2016 13:10:36 UTC