This change support running kubernetes master on Ubuntu Trusty.
It uses pure cloud-config and shell scripts, and completely gets
rid of saltstack or the release salt tarball.
The node.yaml has some logic that will be also used by the kubernetes
master on trusty work (issue #16702). This change moves the code
shared by the master and node configuration to a separate script, and
the master and node configuration can source it to use the code.
Moreover, this change stages the script for GKE use.
It is for running nodes on Ubuntu image upto 14.04 LTS (Trusty).
The change for running master on Ubuntu will be added later.
The configuration consists of several upstart jobs, which is
passed to node instances through GCE metadata and parsed by cloud-init.