Update copyright year to 2018.

llvm-svn: 334936
GitOrigin-RevId: 7555c589af006c9c4d171794200753d0e92ef946
diff --git a/LICENSE.TXT b/LICENSE.TXT
index 666ec55..6453fb6 100644
--- a/LICENSE.TXT
+++ b/LICENSE.TXT
@@ -11,7 +11,7 @@
 
 ==============================================================================
 
-Copyright (c) 2011-2016 by the contributors listed in CREDITS.TXT
+Copyright (c) 2011-2018 by the contributors listed in CREDITS.TXT
 
 All rights reserved.