docs(readme): add note about node-gyp

[skip ci]

Author: Awk34

readme.md

@@ -37,6 +37,7 @@ yo angular-fullstack
 
 * MongoDB - Download and Install [MongoDB](https://www.mongodb.com/download-center#community) - If you plan on scaffolding your project with mongoose, you'll need mongoDB to be installed and have the `mongod` process running.
 * The project's JavaScript is written in ECMAScript 2015. If you're unfamiliar with the latest changes to the specification for JavaScript, check out http://es6-features.org/
+* [`node-gyp`](https://github.com/nodejs/node-gyp) - You'll likely need to be able to use `node-gyp`, Node's tool for compiling native add-ons (for things like database drivers). See its [Installation section](https://github.com/nodejs/node-gyp#installation) for more instructions.
 
 ## Supported Configurations