Remove Chapter 27 from reference documentation (SPR-7433)

Chapter 27 covered @Required and RequiredAnnotationBeanPostProcessor but
did not hold together as a chapter unto itself.  The IoC chapter already
makes mention of @Required and RequiredAnnotationBeanPostProcessor,
though not in quite as much detail as Chapter 27 did.  Links have been
updated throughout to reference these sections and Chatper 27 has been
eliminated entirely.

git-svn-id: https://src.springframework.org/svn/spring-framework/trunk@3559 50f2f4bb-b051-0410-bef5-90022cba6387

spring-framework-reference/src/spring-framework-reference.xml

@@ -453,10 +453,6 @@
         <listitem>
           <para><xref linkend="dynamic-language" /></para>
         </listitem>
-
-        <listitem>
-          <para><xref linkend="metadata" /></para>
-        </listitem>
       </itemizedlist>
     </partintro>
 
@@ -477,8 +473,6 @@
 
     <xi:include href="dynamic-languages.xml"
                 xmlns:xi="http://www.w3.org/2001/XInclude" />
-
-    <xi:include href="metadata.xml" xmlns:xi="http://www.w3.org/2001/XInclude" />
   </part>
 
   <!-- back matter -->