Remove rails start command

- See: learn-co-curriculum/project-template-react-rails-api#33

Author: ihollander

README.md

@@ -31,15 +31,20 @@ To set up your backend, run:
 $ bundle install
 ```
 
-To see how the React application and Rails API are interacting, you can run both
-the Rails application and the React application together by running:
+To see how the React application and Rails API are interacting, you can run the
+Rails application in one terminal by running:
 
 ```console
-$ rails start
+$ rails s
 ```
 
-This will run a Rake task that will start both the Rails app and the React app.
-You must use `rails start` (not `rails s`) to start both applications together!
+Then, open another terminal and run React:
+
+```console
+$ npm start --prefix client
+```
+
+Each application will run on its own port on `localhost`:
 
 - React: [http://localhost:4000](http://localhost:4000)
 - Rails: [http://localhost:3000](http://localhost:3000)