change "All right" to "All rights" (#82)

typo fix on README.adoc

Author: per1234

README.adoc

@@ -16,7 +16,7 @@ https://www.arduino.cc/en/Reference/{repository-name}
 == License ==
 
 Copyright (C) 2006-2008 Hans-Christoph Steiner. All rights reserved.
-Copyright (c) 2010 Arduino LLC. All right reserved.
+Copyright (c) 2010 Arduino LLC. All rights reserved.
 
 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public