Update travis CI to test with firefox latest

[juwara0]

This project uses semver, please check the scope of this pr:

• [X] #none# - documentation fixes and/or test additions
• [ ] #patch# - backwards-compatible bug fix
• [ ] #minor# - adding functionality in a backwards-compatible manner
• [ ] #major# - incompatible API change

CHANGELOG

• Updated travis CI to run against firefox latest

[notmessenger]

👍

[coveralls]

Changes Unknown when pulling 4944116f21b2653889705224498ad86d76bcd3b9 on juwara0:firefoxLatest into on ciena-frost:master.