typo in manual for enablemultiplemappings attribute of copy task

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@275975 13f79535-47bb-0310-9956-ffa450edef68

docs/manual/CoreTasks/copy.html

@@ -119,7 +119,7 @@ operation as <a href="../CoreTypes/filterset.html">filtersets</a>
     attribute if given or the default JVM encoding otherwise.</td>
   </tr>
   <tr>
-    <td valign="top">enablemultiplemapping</td>
+    <td valign="top">enablemultiplemappings</td>
     <td valign="top">
       If true the task will process to all the mappings for a
       given source path. If false the task will only process