Update Copyright year to 2020 in NOTICE files

Changes:
- update Copyright reference year to 2020 in main NOTICE file and in templates for the binary distributions

Reviewers: Nicolò Boschi <boschi1997@gmail.com>, Flavio Junqueira <fpj@apache.org>, Alessandro Luccaroni <luccaronia@gmail.com>, Rajan Dhabalia <rdhabalia@apache.org>

This closes #2428 from eolivelli/fix/update-year-notice

(cherry picked from commit 67a02db73d62188fc8a143bd9a37038ae770e90a)
Signed-off-by: Enrico Olivelli <eolivelli@apache.org>
diff --git a/NOTICE b/NOTICE
index 64cd460..c2788b6 100644
--- a/NOTICE
+++ b/NOTICE
@@ -1,5 +1,5 @@
 Apache BookKeeper
-Copyright 2011-2018 The Apache Software Foundation
+Copyright 2011-2020 The Apache Software Foundation
 
 This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).
diff --git a/bookkeeper-dist/src/main/resources/NOTICE-all.bin.txt b/bookkeeper-dist/src/main/resources/NOTICE-all.bin.txt
index f4739b5..695f378 100644
--- a/bookkeeper-dist/src/main/resources/NOTICE-all.bin.txt
+++ b/bookkeeper-dist/src/main/resources/NOTICE-all.bin.txt
@@ -1,5 +1,5 @@
 Apache BookKeeper
-Copyright 2011-2018 The Apache Software Foundation
+Copyright 2011-2020 The Apache Software Foundation
 
 This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).
diff --git a/bookkeeper-dist/src/main/resources/NOTICE-bkctl.bin.txt b/bookkeeper-dist/src/main/resources/NOTICE-bkctl.bin.txt
index 5d83410..c0c1ba2 100644
--- a/bookkeeper-dist/src/main/resources/NOTICE-bkctl.bin.txt
+++ b/bookkeeper-dist/src/main/resources/NOTICE-bkctl.bin.txt
@@ -1,5 +1,5 @@
 Apache BookKeeper
-Copyright 2011-2018 The Apache Software Foundation
+Copyright 2011-2020 The Apache Software Foundation
 
 This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).
diff --git a/bookkeeper-dist/src/main/resources/NOTICE-server.bin.txt b/bookkeeper-dist/src/main/resources/NOTICE-server.bin.txt
index 1b9a34c..b650cb1 100644
--- a/bookkeeper-dist/src/main/resources/NOTICE-server.bin.txt
+++ b/bookkeeper-dist/src/main/resources/NOTICE-server.bin.txt
@@ -1,5 +1,5 @@
 Apache BookKeeper
-Copyright 2011-2018 The Apache Software Foundation
+Copyright 2011-2020 The Apache Software Foundation
 
 This product includes software developed at
 The Apache Software Foundation (http://www.apache.org/).