Build process for ubuntu-based image

Our main image for development is a Fedora Atomic image pre-built with docker, kubernetes, flannel, etcd. The build process for this image is rather complex and fragile. It is also difficult to install additional packages to help with development.

From the discussion at the Tokyo Design Summit, the team would like to have Ubuntu as another image option for development. The build process for the Ubuntu image will use diskimagebuilder, so we will develop diskimagebuilder elements for installing Flannel, etcd, docker, Kubernetes as systemd services. The image needs to accommodate the current scripts for kubernetes and swarm.

The build process will be documented properly so that anyone can create a new image with new versions.