Update readme

Author: Branor

README.md

@@ -28,7 +28,7 @@ Version Compatibility:
     +------------------------------------------------------------------+
     |  Plugin                       |  Couchbase    | Elasticsearch    |
     +------------------------------------------------------------------+
-    | master                        |  2.5.x - 4.x  | 5.2.1            |
+    | master                        |  2.5.x - 4.x  | 5.3.0            |
     +------------------------------------------------------------------+
     | 2.5.x.y                       |  2.5.x - 4.x  | 5.x.y            |
     +------------------------------------------------------------------+