Node version about meteor-launchpad

[jshimko]

You can build your own copy of meteor-launchpad and specify the NODE_VERSION in this file, but you can't just use whatever version you want. You have to stick with the version that Meteor currently supports. As of right now, that's 4.x. Once Meteor supports something higher, it'll change here too.

I've also debated not even installing Node/npm in this image because Meteor comes packaged with the version it requires (you use it by running meteor node or meteor npm), but the scripts in this project completely delete Meteor after the build, so I went with a separate install if Node/npm.

[ajgarn]

Okay, great answer, I did not know that. Thanks!