Update readme.md

Reflect the change about passing on the **global** `onError()` if it's defined, so we can execute it or not from the **local* `onError()`.

readme.md

@@ -84,7 +84,7 @@ api.config({
     methods: [{
         name: "courses",
         post: "functions/getCourses",
-        onError: function(e, callback){
+        onError: function(e, callback, globalOnError){
         	alert("There was an error getting the courses!");
         }
     }, {
@@ -121,6 +121,38 @@ You can pass the _optional_ **onError** and **onLoad** handlers, which will inte
 
 Note, in the **onError** handler, you can (as of 1.2.0) also handle any network errors better -- in the example above a **retry** method is returned so you can check the error, display a specific one, or handle any network issues, and if required, issue a **retry()** which will attempt the last call again.
 
+If you've defined a **global onError()** within the configuration, it will passed onto any local `onError()` function defined for you methods. This way you can have something like:
+
+```javascript
+     methods: [{
+        name: "courses",
+        post: "functions/getCourses",
+        onError: function(e, callback, globalOnError) {
+		if (e.message) {
+			alert(e.message);
+		} else {
+			globalOnError();
+		}
+        }
+    }, {
+        ...
+    }],
+    onError: function(e, retry) {
+        var dialog = Ti.UI.createAlertDialog({
+            title: "Connection error",
+            message: "There was an error connecting to the server, check your network connection and  retry.",
+            buttonNames: ['Retry']
+        });
+
+        dialog.addEventListener("click", function() {
+            retry();
+        });
+        dialog.show();
+    },
+```
+
+If there is an error message within the response, you'll display it within an `alert()`, otherwise the normal global `onError()` handler will be used.
+
 If you specify parameters required e.g. **videoId** then RESTe will automatically check for these in the parameters passed to the method, and raise an error if they're missing.
 
 Once you've done all this (and assuming no errors), you'll have new methods available: