Travis config updated to contain latest supported versions of Node.js

[ppitonak]

No description provided.

[dougwilson]

Thanks! Unfortunately this isn't the way the Travis versions are done in our org. We usually have the current minor listed for all majors above the package.json listed minimum.

[dougwilson]

Fix the list from the feedback.

[ppitonak]

Do I understand it correctly that you want 4.6, 5.12, 6.9 and 7.1 listed instead of 4, 5, 6, and 7? What about versions that are no longer supported - 0.8, 0.10, 1.x, 2.x, 3.x and 5.x?

[dougwilson]

Yes, list all current minors for all majors above the package.json listed minimum.