MINOR: Update copyright year in NOTICE

Author: Ewen Cheslack-Postava <me@ewencp.org>

Reviewers: Jason Gustafson <jason@confluent.io>, Guozhang Wang <wangguoz@gmail.com>

Closes #4529 from ewencp/update-NOTICE-year

(cherry picked from commit 2d4fb785409056b7abfdfe6082f2862a138acf74)
Signed-off-by: Ewen Cheslack-Postava <me@ewencp.org>
diff --git a/NOTICE b/NOTICE
index 7a62b7f..c97f407 100644
--- a/NOTICE
+++ b/NOTICE
@@ -1,5 +1,5 @@
 Apache Kafka
-Copyright 2017 The Apache Software Foundation.
+Copyright 2018 The Apache Software Foundation.
 
 This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).