Added beginnings of React solution

README.md

@@ -388,3 +388,66 @@ Period:
 ```
 
 Notice this button is bound so it's disabled until we've created the game. It's onClick is bound to the `toggleTimer` method, and the text changes from Start to Stop depending on whether the timer is already started.
+
+
+## Solving this tutorial with React
+
+There's a worked solution to this tutorial using React.js on the `react-solution` branch. But let's talk you through it.
+
+### Some config changes
+
+First, there's some config changes we'll make to make things easier. By default, React won't give you nice error messages -- it left them out of the library to save space. So make the HTML load the development scripts from our node_modules directory:
+
+```html
+<script src="./node_modules/react/umd/react.development.js"></script>
+<script src="./node_modules/react-dom/umd/react-dom.development.js"></script>
+```
+
+And tell webpack not to put React itself into bundle.js (because we're loading its development scripts separately). In webpack.config.js, inside `module.exports`:
+
+```js
+externals: {
+  "react": "React",
+  "react-dom": "ReactDOM"
+}
+```
+
+We're also going to want to use TSX, so let's update compilerOptions in `tsconfig.json`:
+
+```js
+    "jsx": "react"
+```
+
+And let's also rename `index.ts` to `index.tsx`, and then update `webpack.congfig.js` to tell it about the new entry point:
+
+```js
+  entry: './src/index.tsx',
+```
+
+### Getting React on-screen
+
+Let's get React rendering something, even if just Hello World. 
+
+In index.html, create a div that Vue can render to. Let's put this above the svg for the game:
+
+```html
+<div id="app"></div>
+```
+
+And inside index.tsx, let's import React and ReactDOM, and something to that div
+
+```ts
+import * as React from "react";
+import * as ReactDOM from "react-dom";
+```
+
+and now for our first bit of TSX:
+
+```ts
+ReactDOM.render(
+    <div>Hello React</div>,
+    document.getElementById("app")
+);
+```
+
+Reload, and check we get "Hello Vue" appearing. If so, good -- React is working, can compile templates, and we can progress.