allow ref to default xml config from wiki snippet, got lost in the tidying up of the config

git-svn-id: https://svn.apache.org/repos/asf/activemq/trunk@1021484 13f79535-47bb-0310-9956-ffa450edef68

assembly/src/release/conf/activemq.xml

@@ -14,6 +14,7 @@
     See the License for the specific language governing permissions and
     limitations under the License.
 -->
+<!-- START SNIPPET: example -->
 <beans
   xmlns="http://www.springframework.org/schema/beans"
   xmlns:amq="http://activemq.apache.org/schema/core"
@@ -133,3 +134,4 @@
     <import resource="jetty.xml"/>
     
 </beans>
+<!-- END SNIPPET: example -->