Update Joda Time references in documentation

Update documentation to reflect the fact that Joda Time is no longer
required to use the @DateTimeFormat annotation.

src/reference/docbook/mvc.xml

@@ -4609,8 +4609,7 @@ public class WebConfig {
             <para>Support for <link linkend="format">formatting</link> Date,
             Calendar, Long, and Joda Time fields using the 
             <interfacename>@DateTimeFormat</interfacename>
-            annotation, if Joda Time 1.3 or higher is present on the
-            classpath.</para>
+            annotation.</para>
           </listitem>
 
           <listitem>