docs(readme): add info about mongodb

Author: DaftMonk

Diff for: readme.md

@@ -17,6 +17,10 @@ Generated by saying yes to all questions: http://fullstack-demo.herokuapp.com/.
 
 Have a look at the source code: https://github.com/DaftMonk/fullstack-demo
 
+## Prerequisites
+
+* MongoDB - Download and Install [MongoDB](http://www.mongodb.org/downloads) - If you plan on scaffolding your project with mongoose, you'll need mongoDB to be installed.
+
 ## Usage
 
 Install `generator-angular-fullstack`: