Update for Node.js v4.7.1 and v6.9.3

[chorrell]

See:

• https://nodejs.org/en/blog/release/v4.7.1/
• https://nodejs.org/en/blog/release/v6.9.3/

[chorrell]

Hi @nodejs/docker

Can someone review this? Also note that the test build actually completed and was successful:

• https://travis-ci.org/nodejs/docker-node/builds/188713778

[tomgco]

I am not a member of nodejs/docker, however I have tested and ran all locally and they seems fine for me.

[chorrell]

I'll work on the PR for the Docker Hub this afternoon.

[chorrell]

Actually...I'll do the Docker Hub PR once #304 lands :)