Allow node-builder image to checkout from private source repositories

[rocketeerbkw]

If a project has node modules that require compilation, the node-builder is the only image with the required packages to support that.

If a project has private node modules that are checked out of source control (not via npmjs.com), the node-cli is the only image with the required packages to support that.

There needs to be an image that can do both. I think there are a couple options:

1. Move everything from node-builder into node-cli.
   This matches closer to the php example, where the cli image is used for all code requirements (checkout, composer, etc) and only the necessary assets are moved into the node image that serves the production assets. The downside is all the "build" packages live in node-cli after building.

2. Copy all the needed config from node-cli into node-builder.
   Lots of duplication, unclear when to use cli vs builder. Most backwards compatible?

3. Change so that builder image is built from cli image.
   Removes code duplication, I don't think it makes have a builder + cli setup any easier though.