Open source cloud-config of DO official images

[pascalandy]

I use Docker a lot and the project is updating very quickly.

The DO image is not following the standard installation setup. i.e. 8) Save and close the /etc/apt/sources.list.d/docker.list file. is not set so it's a pain to update Docker.

It would be awesome to open source the scripts you are using to create DO images. The community would improve it and we could all make sure we are using best practice for the Docker image.

Thanks!