Add link to Contributors page on wiki from the main OSM copyright page.

config/locales/en.yml

@@ -1139,6 +1139,12 @@ en:
           2010.</li>
       </ul>
 
+      <p>
+        For further details of these, and other sources that have been used
+        to help improve OpenStreetMap, please see the <a
+        href="http://wiki.openstreetmap.org/wiki/Contributors">Contributors
+        page</a> on the OpenStreetMap Wiki.
+      </p>
       <p>
         Inclusion of data in OpenStreetMap does not imply that the original
         data provider endorses OpenStreetMap, provides any warranty, or