Updated README

README.md

@@ -28,7 +28,17 @@ In the hosting application, a configuration file, for example
   security_token: xxxxxxxxxxxxx
   client_id: xxxxxxxxxxxxxxxxxxxx
   client_secret: xxxxxxxxxxxxxx
-  api_version: '24.0'
+  api_version: '41.0'
+```
+Or
+```
+host: <%= ENV["SF_HOST"] %>
+username: <%= ENV["SF_USERNAME"] %>
+password: <%= ENV["SF_PASSWORD"] %>
+security_token: <%= ENV["SF_SECURITY_TOKEN"] %>
+client_id: <%= ENV["SF_CLIENT_ID"] %>
+client_secret: <%= ENV["SF_CLIENT_SECRET"] %>
+api_version: <%= ENV["SF_API_VERSION"] %>
 ```
 
 Please refer to [https://github.com/ejholmes/restforce](https://github.com/ejholmes/restforce) for the detail.