update end year to 2019 (#79)

diff --git a/NOTICE.txt b/NOTICE.txt
index 586a653..96cc3b4 100644
--- a/NOTICE.txt
+++ b/NOTICE.txt
@@ -1,5 +1,5 @@
 Apache OpenWhisk Runtime Java
-Copyright 2016-2018 The Apache Software Foundation
+Copyright 2016-2019 The Apache Software Foundation
 
 This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).