Changed manage_copyright link description from "Digital Creations" to "Zope...

Changed manage_copyright link description from "Digital Creations" to "Zope Corporation".  Still need to figure out what to do about manage_copyright itself, as it contains a license and I'm afraid to change it.

lib/python/App/dtml/menu.dtml

@@ -49,7 +49,7 @@ td {
   <td valign="top" nowrap>
   <strong>
   <a href="manage_copyright" target="manage_main">
-  &copy; Digital Creations
+  &copy; Zope Corporation
   </a>
   </strong>
   </td>