chore(readme): Add NPM installation instructions

Closes #3991

Author: Foxandxss

Diff for: README.md

@@ -7,6 +7,7 @@
 ### Quick links
 - [Demo](#demo)
 - [Installation](#installation)
+    - [NPM](#install-with-npm)
     - [Bower](#install-with-bower)
     - [NuGet](#install-with-nuget)
     - [Custom](#custom-build)
@@ -29,6 +30,14 @@ Do you want to see directives in action? Visit http://angular-ui.github.io/boots
 Installation is easy as UI Bootstrap has minimal dependencies - only the AngularJS and Twitter Bootstrap's CSS are required.
 Note: Since version 0.13.0, UI Bootstrap depends on [ngAnimate](https://docs.angularjs.org/api/ngAnimate) for transitions and animations, such as the accordion, carousel, etc. Include `ngAnimate` in the module dependencies for your app in order to enable animation.
 
+#### Install with NPM
+
+```sh
+$ npm install angular-ui-bootstrap
+```
+
+This will install AngularJS and Bootstrap NPM packages.
+
 #### Install with Bower
 ```sh
 $ bower install angular-bootstrap
@@ -61,6 +70,14 @@ When you are done downloading all the dependencies and project files the only re
 angular.module('myModule', ['ui.bootstrap']);
 ```
 
+If you're a Browserify or Webpack user, you can do:
+
+```js
+var uibs = require('angular-ui-bootstrap');
+
+angular.module('myModule', [uibs]);
+```
+
 # Support
 
 ## FAQ