update license: copyright years, add myself as netsem team member

Author: hannesm

LICENSE

@@ -1,12 +1,12 @@
-This collection of files, "the Netsem specification as of November 2011",
-referred to as the "program" below, are copyright:
+This collection of files, "the Netsem specification", referred to as the
+"program" below, are copyright:
 
-    Copyright (C) 2005-2011 The Netsem Team:
-      Steve Bishop, Matthew Fairbairn, Michael Norrish, Tom Ridge,
-      Peter Sewell, Michael Smith, Keith Wansbrough
+    Copyright (C) 2005-2019 The Netsem Team:
+      Steve Bishop, Matthew Fairbairn, Hannes Mehnert, Michael Norrish,
+      Tom Ridge, Peter Sewell, Michael Smith, Keith Wansbrough
 
 This program is free software; you can redistribute it and/or modify
-it under the terms of the Simplified BSD License as below. 
+it under the terms of the Simplified BSD License as below.
 
 Other licensing terms may be available; please contact us if necessary:
 
@@ -25,7 +25,7 @@ The Simplified BSD License is reproduced below.
 
 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
 
-Copyright (c) 2005-2011, the Netsem Team
+Copyright (c) 2005-2019, the Netsem Team
 All rights reserved.
 
 Redistribution and use in source and binary forms, with or without