Update README with 7th lesson on universal rendering with Redux

The seventh lesson goes over how to set up Redux isomorphically
(on the server as well as the client).

Save dependencies `redux` and `react-redux`.

Create a reducer that returns just the default state and create
a Redux store with the initial state of the server data.

Surround the routes (on both server and client) with <Provider>
and remove the Router's `createElement` prop.

Refactor <Layout> and wrap it with ReactRedux `connect`.

Also, update webpack config to transpile both `.js` and `.jsx`
files (JSX is used in `client.js`).

YouTube:
- Title: Universal rendering with React and Redux
- Link: https://www.youtube.com/watch?v=XXjb7C7eBa8

Author: remarkablemark

README.md

@@ -7,13 +7,13 @@ The web application is built with:
 - [Express](https://b.remarkabl.org/1WhuaOl)
 - [React](https://b.remarkabl.org/24739fL)
 - [ReactRouter](https://b.remarkabl.org/2dhSEVJ)
+- [Redux](https://b.remarkabl.org/2gU9dHt) and [ReactRedux](https://b.remarkabl.org/2gBtLbs)
 
-## Installation
+## Download
 
 ```sh
 $ git clone https://github.com/remarkablemark/universal-react-tutorial.git
 $ cd universal-react-tutorial
-$ npm install
 ```
 
 ## Tutorials
@@ -22,41 +22,55 @@ $ npm install
 
 ```sh
 $ git checkout v1
+$ npm install
 $ npm start
 ```
 
 [2. Building a universal/isomorphic app with React](https://b.remarkabl.org/1XKYMqp):
 
 ```sh
 $ git checkout v2
+$ npm install
 $ npm start
 ```
 
 [3. Passing props in a universal React web app](https://b.remarkabl.org/1UfmGeA):
 
 ```sh
 $ git checkout v3
+$ npm install
 $ npm start
 ```
 
 [4. Server-side routing with react-router](https://b.remarkabl.org/2dCiZ06):
 
 ```sh
 $ git checkout v4
+$ npm install
 $ npm start
 ```
 
 [5. Client-side routing with react-router (Part 1)](https://b.remarkabl.org/2faLHsH):
 
 ```sh
 $ git checkout v5
+$ npm install
 $ npm start
 ```
 
 [6. Client-side routing with react-router (Part 2)](https://b.remarkabl.org/2fOOWn7):
 
 ```sh
 $ git checkout v6
+$ npm install
+$ npm start
+```
+
+[7. Universal rendering with React and Redux](https://b.remarkabl.org/2hybtYR):
+
+```sh
+$ git checkout v7
+$ npm install
 $ npm start
 ```