Move "Launch an Instance" to end of Install Guide

Moved the "Launch an Instance" section to the bottom of the
install guide, to prevent readers from having to jump around
from later chapters.  Also added a note at the end of every
chapter, starting with the Networking chapter, letting them
know that they can launch an instance or add additional
features.

Change-Id: Ie356370bb1a1efa28e36f8f2e25fdc3fff8b35d6
Implements: networking-install-guide-improvements
Closes-Bug: 1301180