update license of checkstyle task.

git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@271144 13f79535-47bb-0310-9956-ffa450edef68

docs/external.html

@@ -321,7 +321,10 @@
                       <td bgcolor="#a0ddf0" colspan="" rowspan="" 
       valign="top" align="left">
     <font color="#000000" size="-1" face="arial,helvetica,sanserif">
-          GNU General Public License
+          Releases 1.0 to 1.4 have been licensed under the GNU
+            General Public License.  Starting with release 2.0 the
+            license has been changed to the GNU Lesser General Public
+            License.
         </font>
   </td>
       </tr>

xdocs/external.xml

@@ -98,7 +98,10 @@
           </tr>
           <tr>
             <th>License:</th>
-            <td>GNU General Public License</td>
+            <td>Releases 1.0 to 1.4 have been licensed under the GNU
+            General Public License.  Starting with release 2.0 the
+            license has been changed to the GNU Lesser General Public
+            License.</td>
           </tr>
         </table>
       </subsection>