Update copyright year

Hugo Osvaldo Barrera · Hugo Osvaldo Barrera · commit 289f60da44ee · 2020-06-08T19:58:35.000+02:00
diff --git a/LICENSE b/LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2014-2016 by Markus Unterwaditzer & contributors. See
+Copyright (c) 2014-2020 by Markus Unterwaditzer & contributors. See
 AUTHORS.rst for more details.
 
 Some rights reserved.

Original file line number	Diff line number	Diff line change
`@@ -1,4 +1,4 @@`
`1`		`-Copyright (c) 2014-2016 by Markus Unterwaditzer & contributors. See`
	`1`	`+Copyright (c) 2014-2020 by Markus Unterwaditzer & contributors. See`
`2`	`2`	`AUTHORS.rst for more details.`
`3`	`3`
`4`	`4`	`Some rights reserved.`