Fix minor problems and polish reference docs

Problems

 - Eliminate — in favor of —

   — was causing 'no such entity' errors during docbook
   processing; — produces the equivalent output.

 - Fix column issues in appendices

   column counts were set to 3, when they are in fact 4. This passed
   under DocBook 4 and Spring Build for unknown reasons, but caused a
   hard stop under DocBook 5 and the docbook-reference-plugin.

 - Add jdbc callout section in docbook 5-friendly style

   use <co/> tags as advertised in DocBook documentation.

 - Set correct widths for PDF ref doc images

   images were rendering larger than the PDF page; just set all to
   width=400 and everything looks good.

Polish

 - Update reference doc copyright to 2012

 - Remove "work-in-progress" language from ref docs

 - Update maven URLs to repo.springsource.org

 - Update javadoc urls from 3.0.x/javadoc-api => current/api

 - Replace hardcoded "3.1" with ${version} in ref doc

src/reference/docbook/transaction.xml

@@ -718,7 +718,8 @@ TR: OK AS IS. images don't show up in the editor, but they do show up in the gen
 
       <para><mediaobject>
           <imageobject role="fo">
-            <imagedata align="center" fileref="images/tx.png" format="PNG" />
+            <imagedata align="center" fileref="images/tx.png" format="PNG"
+                width="400"/>
           </imageobject>
 
           <imageobject role="html">
@@ -1847,13 +1848,18 @@ TR: REVISED, PLS REVIEW - changed it back; it's not just settings, the section d
         <title>Required</title>
 
         <para><mediaobject>
-            <imageobject>
+            <imageobject role="fo">
               <imagedata align="center" fileref="images/tx_prop_required.png"
-                         format="PNG" />
+                  format="PNG" width="400"/>
             </imageobject>
 
-            <caption><para>PROPAGATION_REQUIRED</para></caption>
-          </mediaobject></para>
+            <imageobject role="html">
+              <imagedata align="center" fileref="images/tx_prop_required.png"
+                  format="PNG" width="400"/>
+            </imageobject>
+
+              <caption><para>PROPAGATION_REQUIRED</para></caption>
+            </mediaobject></para>
 
         <para>When the propagation setting is
         <literal>PROPAGATION_REQUIRED</literal>, a