Add The Road to Learn React [pt-br] (#3117)

* Update free-programming-books-pt_BR.md

Add the book "The Road to Learn React"

* Add the the notation "Leanpub account or valid email requested"

free-programming-books-pt_BR.md

@@ -180,6 +180,7 @@
 #### React
 
 * [React: JavaScript reativo](http://tableless.com.br/react-javascript-reativo/)
+* [The Road to Learn React](https://leanpub.com/the-road-to-learn-react-portuguese) *(necessário conta no Leanpub ou e-mail válido)*
 
 
 #### Vue.js