Create React App with multiple entry points

Attention: It's an ejected version of create-react-app, however, I'm going to push a PR for this missing feature. The non ejected version could be find here: https://github.com/DanZeuss/create-react-app

There's a pending PR for this solution on facebook/create-react-app#8249

To add more entry points, follow the steps:

• Before cloning, please, slap ⭐️ now
• Add a new page in the package.json in the property appPages. There are 2 existing pages there: index and login;
• Create your new files for the new page. You should add a new .html file inside the public folder and also add your new .js file (related to your "new" app) inside your src folder.
• Run yarn start or npm start;
• Access your using the following url /.hml, for example: http://localhost:3000/login.html