add StateFunction to README

README.md

@@ -72,6 +72,17 @@ let result = Jsste.render(pagecode, templatecode);
 - `_TEMPLATE_` -> Defines the path to the temp file
 - `_STYLES_` -> Defines a list of CSS files that will be implemented
 
+### Include States
+
+You can include an Callbackfunction that will be called when the state is change
+
+```javascript
+jsste.setStateFunction(({ status, statusMSG }) => {
+  yourstatus = status;
+  yourstatusMSG = statusMSG;
+});
+```
+
 ### States-Codes
 
 | Code | Meaning |