Release procedure changes & nominating @sam-github and @jasnell as releasers #2416

I'm proposing that we fully unify the release process for 0.10, 0.12, io.js, 4.x+ and LTS. Initially I thought that having separate groups for different concerns was the way to go but now I think that's over-optimising and we should just reduce friction and let people gravitate towards the release lines that they are more concerned with—if we have a big enough group of releasers then we should be covered. I also think our current procedures for getting sign-off via GitHub is suffice to stop any unwanted changes getting out into LTS & Maintainence where we need to take much more care.

Current status:

• 0.10 and 0.12 have been handled previously by @misterdjules and now @sam-github and @jasnell have been given access & instructions on how to do this. @cjihrig also expressed interest in helping out there. @misterdjules would rather not be responsible for releases.
• io.js releases have been handled by @chrisdickinson, @Fishrock123, @cjihrig and myself and our GPG keys are currently the only ones listed on the nodejs/node README which is obviously inaccurate for "Node.js".
• Node.js v4 hasn't had any releases yet so we don't have this fully sorted out. LTS hasn't started yet so that's only been briefly discussed and nothing more.

I propose that we:

1. Put @sam-github, @jasnell, @chrisdickinson, @Fishrock123, @cjihrig and myself on the @nodejs/release team
2. Add GPG key fingerprints for @sam-github and @jasnell on the README here, for historical accuracy we should also list fingerprints for Isaac, TJ and Julien somewhere on there too
3. Add the ssh keys of the entire @nodejs/release team to the new incarnation of nodejs.org so they can perform the full release procedure for any release line (exactly how this will work is still under consideration and will be some kind of mash-up of the joyent/node procedure with the io.js procedure)
4. Add the GPG key fingerprints of the @nodejs/release team to the Dockerfiles /cc @nodejs/docker

Relevant docs on how it's currently handled:

• joyent/node: https://github.com/joyent/node/wiki/Node.js-release-guide
• io.js: https://github.com/nodejs/node/blob/master/doc/releases.md

Tagging this as tsc-agenda because it'll need formal sign-off. @sam-github and @jasnell may choose to decline, and all of this is up for discussion by collaborators as well of course.