Update copyright for 2016.

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/net/trunk@1725371 13f79535-47bb-0310-9956-ffa450edef68
diff --git a/NOTICE.txt b/NOTICE.txt
index a3d7740..66e7099 100644
--- a/NOTICE.txt
+++ b/NOTICE.txt
@@ -1,5 +1,5 @@
 Apache Commons Net
-Copyright 2001-2015 The Apache Software Foundation
+Copyright 2001-2016 The Apache Software Foundation
 
 This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).