Fix inconsistent sentence on FlatDHCP description

Change sentences order to clarify that DHCP servers are started
and configured by the node running nova-network.

Change-Id: I7e8b82375323ca61e90cef95ca84f66c4cb678e5
backport: none
Closes-Bug: #1157670
Add glossary to Install Guide

This adds a small glossary to the Install Guide. The glossary
is produced from all entries that use <firstterm> or
<glossterm> and which are in the global glossary (see file
glossary/gloss-terms.xml).

I (dcramer) have patched this to work if built against
https://review.openstack.org/68416, which fixes the
problem where the glossary wasn't populated in the pdf.

Updates to clouddocs-maven-plugin 1.13.0 that has dcramer's fix.

Change-Id: I357265ea99a7e9b0f4004ef529a2043605e8b2ec
Merge "Add glossary to Install Guide"
Merge "Fix inconsistent sentence on FlatDHCP description"