Updated README.txt

Author: Wee Hyong Tok

Samples/JSONConversionTool/README.txt

@@ -5,5 +5,5 @@ Where:
 /sd <source directory>  -  Source Directory containing JSON definitions.
 /td <target directory>  -  Target Directory for new Upgraded JSON defintions. 
 /v <target API version> -  This is an optional argument. 
-                           By default latest API version: '2015-05-01-preview' will be assumed. 
-                           Supported target API versions: 2014-12-01-preview, 2015-01-01-preview, 2015-05-01-preview.
+                           By default latest API version: '2015-07-01-preview' will be assumed. 
+                           Supported target API versions: 2014-12-01-preview, 2015-01-01-preview, 2015-05-01-preview, 2015-07-01-preview.