Upgrade to node 4.8.5, 6.11.5, and 8.8.0 with yarn 1.2.1 to fix a DOS security vulnerability

[pokle]

See https://nodejs.org/en/blog/vulnerability/oct-2017-dos/

[pokle]

The build failed because it timed out doing a docker pull of a dependency. How do I restart the travis build? https://travis-ci.org/nodejs/docker-node/builds/292447040

[SimenB]

Our policy states that yarn should be updated on all new node releases, so I reverted that commit. (https://github.com/nodejs/docker-node/blob/master/CONTRIBUTING.md#version-updates)

I also updated the script we use for generating PRs to docker hub.

Other than that, I'll merge as soon as CI is green 🙂

Thanks!

[SimenB]

@tianon @yosifkit We're seeing timeouts on CI doing at the first stage FROM buildpack-deps:*. Is that a known issue? It seems to progress after ~5-6 minutes, but not always, making travis kill it for being unresponsive

@nodejs/docker Thoughts on merging regardless of CI timeout?

EDIT: Node@6 build just timed out on the same thing

EDIT2: And there 4 & 8 timed out as well

I'm gonna merge this in 1 hour unless someone yells at me not to (11:30 CEST)

[SimenB]

docker-library/official-images#3621

Thanks @pokle!