Update link to README.

File was moved in https://github.com/apache/brooklyn-client/commit/6fc8a1ee098fa5a4cd7d8fe726dcc7354abaf15a
diff --git a/README.md b/README.md
index 7d5cc7b..d643d6a 100644
--- a/README.md
+++ b/README.md
@@ -90,7 +90,7 @@
 
 ## Running
 
-See instructions in the included [Runtime README](README) file.
+See instructions in the included [Runtime README](release/files/README) file.
 
 ----
 Licensed to the Apache Software Foundation (ASF) under one