Adds starting point for Architecture and Design Guide

The areas that still need work are:
- needs double-checking for tables
- see http://docs.openstack.org/arc/OpenStackArchitectureDesignGuide.epub
  for intended structure

Co-Authored-By: Nick Chase <nchase@mirantis.com>
Co-Authored-By: Beth Cohen <beth.cohen@verizon.com>
Co-Authored-By: Sean Collins <sean_collins2@cable.comcast.com>
Co-Authored-By: Steve Gordon <sgordon@redhat.com>
Co-Authored-By: Sebastian Gutierrez <segutier@redhat.com>
Co-Authored-By: Kevin Jackson <Kevin.Jackson@rackspace.co.uk>
Co-Authored-By: Scott Lowe <slowe@vmware.com>
Co-Authored-By: Maish Saidel-Keesing <msaidelk@cisco.com>
Co-Authored-By: Alexandra Settle <alexandra.settle@rackspace.com>
Co-Authored-By: Vinny Valdez <vvaldez@redhat.com>
Co-Authored-By: Anthony Veiga <Anthony_Veiga@cable.comcast.com>
Co-Authored-By: Sean Winn <sean.winn@cloudscaling.com>

Change-Id: Ia0ca278cd5d2d0ee67b9b7528870c1a2a80fdadf

doc/arch-design/ch_specialized.xml

@@ -0,0 +1,17 @@
+<?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="specialized">
+    <title>Specialized Cases</title>
+
+    <xi:include href="specialized/section_introduction_specialized.xml"/>
+    <xi:include href="specialized/section_multi_hypervisor_specialized.xml"/>
+    <xi:include href="specialized/section_networking_specialized.xml"/>
+    <xi:include href="specialized/section_software_defined_networking_specialized.xml"/>
+    <xi:include href="specialized/section_desktop_as_a_service_specialized.xml"/>
+    <xi:include href="specialized/section_openstack_on_openstack_specialized.xml"/>
+    <xi:include href="specialized/section_hardware_specialized.xml"/>
+
+</chapter>