Update README.md

Author: matheusmr13

README.md

@@ -1,2 +1,14 @@
 # app-script-api
-Create ES6 classes that reproduces exactly Google App Script API (without implementation)
+Create ES6 classes that reproduces exactly [Google App Script](https://developers.google.com/apps-script/) API (without implementation)
+
+## Description
+This project was create to programmatically [generate](https://github.com/matheusmr13/meta-class) ES6 classes based on services that [Google App Scripts](https://developers.google.com/apps-script/) uses to create their real time autocomplete documentation.
+
+## How to use
+1. Clone repo
+2. Install `node >= 5`
+3. `$node getSpreadsheetDocs.js`
+4. All your classes (without implementation) are now on `./classes/`
+    
+## Why
+  Motivated by [this repo](https://github.com/matheusmr13/app-script-mock) used to create mocks to [Google App Scripts](https://developers.google.com/apps-script/)