update README to refer to COPYRIGHT.txt

Change-Id: I32685ef02c245557315a3e44c65eb8c8cf62f9f4
diff --git a/README.md b/README.md
index 282fd5f..e9a5d32 100755
--- a/README.md
+++ b/README.md
@@ -34,7 +34,7 @@
 ## License

 This work is released as open source under a Apache-style license from Khronos including a Khronos copyright.

 

-See LICENSE.txt for a full list of licenses used in this repository.

+See COPYRIGHT.txt for a full list of licenses used in this repository.

 

 ## Acknowledgements

 While this project has been developed primarily by LunarG, Inc; there are many other