Restructured networking portions of installation guide

As part of the installation guide improvement project, I performed
the following operations on the networking portions of the
installation guide:

1) Created "generic networking" chapter directly after Nova chapter.
2) Migrated Neutron chapter to "generic networking" chapter.
3) Migrated "configure networking" section of Nova chapter to
   "generic networking" chapter.
4) Temporarily unlinked "Neutron deployment use cases" section of
   Neutron chapter.
5) Modified links affected by these changes.

This patch primarily addresses structural changes to improve
document flow. Future patches will address content affected by
these changes.

Change-Id: Ib1b12c8d902db1c0ab3cbee9b9fef34b7c8157ac
Partial-Bug: #1291071
Implements: blueprint networking-install-guide-improvements

doc/install-guide/bk_openstackinstallguide.xml

@@ -189,10 +189,10 @@
     <xi:include href="ch_clients.xml"/>
     <xi:include href="ch_glance.xml"/>
     <xi:include href="ch_nova.xml"/>
+    <xi:include href="ch_networking.xml"/>
     <xi:include href="ch_horizon.xml"/>
     <xi:include href="ch_cinder.xml"/>
     <xi:include href="ch_swift.xml"/>
-    <xi:include href="ch_neutron.xml"/>
     <xi:include href="ch_heat.xml"/>
     <xi:include href="ch_ceilometer.xml"/>
     <xi:include href="app_reserved_uids.xml"/>

doc/install-guide/ch_networking.xml

@@ -0,0 +1,32 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<chapter xmlns="http://docbook.org/ns/docbook"
+  xmlns:xi="http://www.w3.org/2001/XInclude"
+  xmlns:xlink="http://www.w3.org/1999/xlink" version="5.0"
+  xml:id="ch_networking">
+  <title>Add a networking service</title>
+<!-- FIXME Temporarily replacing this warning.
+  <warning>
+    <para>This chapter is a bit more adventurous than we would
+      like. We are working on cleanup and improvements to it.
+      Like for the rest of the Installation Guide, feedback
+      through bug reports and patches to improve it are
+      welcome.</para>
+  </warning>
+-->
+  <warning>
+    <para>We are updating this material for Icehouse. You may find structure
+      and/or content issues during this process.</para>
+  </warning>
+  <section xml:id="section_neutron-networking">
+    <title>Networking (neutron)</title>
+    <xi:include href="section_neutron-concepts.xml"/>
+    <xi:include href="section_neutron-controller-node.xml"/>
+    <xi:include href="section_neutron-network-node.xml"/>
+    <xi:include href="section_neutron-compute-node.xml"/>
+    <xi:include href="section_neutron-initial-networks.xml"/>
+  </section>
+  <section xml:id="section_nova-networking">
+    <title>Legacy networking</title>
+    <xi:include href="section_nova-networking-compute-node.xml"/>
+  </section>
+</chapter>

doc/install-guide/ch_nova.xml

@@ -9,6 +9,6 @@
   <xi:include href="section_nova-controller.xml"/>
   <xi:include href="section_nova-compute.xml"/>
   <!--  <xi:include href="section_nova-kvm.xml"/>-->
-  <xi:include href="section_nova-network.xml"/>
+  <!-- <xi:include href="section_nova-network.xml"/> -->
   <xi:include href="section_nova-boot.xml"/>
 </chapter>

doc/install-guide/ch_overview.xml

@@ -83,7 +83,8 @@
         </itemizedlist>
         <note>
           <para>When you implement this architecture, skip
-            <xref linkend="ch_neutron" />. To use optional services, you
+            <xref linkend="section_neutron-networking" /> in
+            <xref linkend="ch_networking" />. To use optional services, you
             might need to install additional nodes, as described in
             subsequent chapters.</para>
         </note>
@@ -134,9 +135,10 @@
         </itemizedlist>
         <note>
           <para>When you implement this architecture, skip
-            <xref linkend="nova-network" /> in <xref linkend="ch_nova" />.
+            <xref linkend="section_nova-networking" /> in
-            To use optional services, you might need to install additional
+            <xref linkend="ch_networking" />. To use optional services, you
-            nodes, as described in subsequent chapters.</para>
+            might need to install additional nodes, as described in
+            subsequent chapters.</para>
         </note>
         <figure xml:id="example-architecture-with-neutron-networking">
           <title>Three-node architecture with OpenStack Networking (neutron)</title>

doc/install-guide/section_nova-networking-compute-node.xml

@@ -17,19 +17,6 @@
     functionality across multiple hosts. As a result, no single
     network controller acts as a single point of failure. This process
     configures each compute node for networking.</para>
-  <note>
-    <para>Choose one of these options to configure networking in OpenStack:</para>
-    <itemizedlist>
-      <listitem>
-        <para>Legacy networking in OpenStack Compute, which is
-          described here.</para>
-      </listitem>
-      <listitem>
-        <para>The full software-defined networking stack. See <xref
-            linkend="ch_neutron"/>.</para>
-      </listitem>
-    </itemizedlist>
-  </note>
   <procedure>
     <step>
       <para>Install the appropriate packages for compute networking on the