add to readme

Readme.md

@@ -3,3 +3,6 @@ A couple of react samples I put together for a presentation.
 You can cd into each directory and run `npm run start` to start the apps up and see them live.
 
 
+[helloworld](./helloworld) - is a simple example of a component that just says hello world
+[helloworld-counter](./helloworld-counter) - is a more complex example of a react component with a button which increments an integer in the dom
+[helloworld-redux-counter](./helloworld-redux-counter) - is the previous example, but the button fires an event which updates the state in redux