Update React example to use Component.driver syntax (krakenjs#224)

This updates the React example snippet to match the example on `docs/api.md`. I don't believe that Zoid has a `react` property on the Component instance anymore, so this updates it to use `Component.driver` and specifies react as the framework.

docs/example.md

@@ -128,10 +128,17 @@ set up bindings for these frameworks:
 
 Drop the component in any `render()` method:
 
+```javascript
+let MyReactLoginComponent = MyLoginComponent.driver('react', {
+    React:    React, 
+    ReactDOM: ReactDOM
+});
+```
+
 ```javascript
 render: function() {
     return (
-        <MyLoginComponent.react prefilledEmail='[email protected]' onLogin={onLogin} />
+        <MyReactLoginComponent prefilledEmail='[email protected]' onLogin={onLogin} />
     );
 }
 ```