Add comments about the last changes concerning the <different> selector

PR: 20205


git-svn-id: https://svn.apache.org/repos/asf/ant/core/trunk@274616 13f79535-47bb-0310-9956-ffa450edef68

WHATSNEW

@@ -136,6 +136,13 @@ Fixed bugs:
   on the user specified classpath when a timeout occured.  Bugzilla
   Report 19953.
 
+* <different> selector : make ignoreFileTimes effectively default to true
+  and fix a bug in the comparison of timestamps. Bugzilla Report 20205
+
+* <different> selector can now be nested directly under a fileset 
+  Bugzilla Report 20220. Documentation of the different selector
+
+
 Other changes:
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 * Six new Clearcase tasks added.