Update to v1.6.4

[Starefossen]

This PR updates the installed io.js version in all Dockerfiles to v1.6.4.

Related: nodejs/node#1340

[jbergstroem]

Isn't this a bit premature? The release isn't out yet (meaning we can't verify that the PR works).

[Starefossen]

Well, considering that there are no other routine in place to update the Dockerfiles when new io.js versions are released – this PR is intended to notify the Docker WG that a new version of io.js is in the works as per the release proposal in nodejs/node#1340.

This PR can of course not be merged until the binaries has shipped and the image is tested. Thus I see no problem in having the PR ready for the pending release.

Also, updating this repo does not automatically update the actual images up at Docker Hub.

[pesho]

this PR is intended to notify the Docker WG that a new version of io.js is in the works

Alternatively, there is a feed available for io.js releases at https://github.com/iojs/io.js/releases.atom. WG members can subscribe to it.

Creating PRs before the actual release has some disadvantages:

• update.sh can't be used for an automatic update. It must be done manually, which is error-prone and not as easy.
• The PR can't be tested before it's submitted.
• Version numbers are not always known in advance. Even if originally planned as a PATCH release, a change may turn out to require a MINOR or MAJOR version bump. This has happened in the past.

[retrohacker]

Also, moving forward there will be a CI server for this repo, and this practice will break that.

[Starefossen]

Valid points. Moving forward we should maybe also set up a hook which opens a new PR when new versions are released. Should be pretty straight forward with Github release event webhook.

[retrohacker]

@Starefossen I had the same thought 😄, I was going to make this part of the CI server.

[pesho]

v1.6.4 is out.

docker-library PR: docker-library/official-images#649