Merge pull request twbs#18530 from twbs/npm-install-bootstrap-at-3

Docs: Include major version in `npm install bootstrap` commands

README.md

@@ -32,7 +32,7 @@ Several quick start options are available:
 * [Download the latest release](https://github.com/twbs/bootstrap/archive/v3.3.6.zip).
 * Clone the repo: `git clone https://github.com/twbs/bootstrap.git`.
 * Install with [Bower](http://bower.io): `bower install bootstrap`.
-* Install with [npm](https://www.npmjs.com): `npm install bootstrap`.
+* Install with [npm](https://www.npmjs.com): `npm install bootstrap@3`.
 * Install with [Meteor](https://www.meteor.com): `meteor add twbs:bootstrap`.
 * Install with [Composer](https://getcomposer.org): `composer require twbs/bootstrap`.
 

docs/_includes/getting-started/download.html

@@ -46,7 +46,7 @@ <h2 id="download-bower">Install with Bower</h2>
 
   <h2 id="download-npm">Install with npm</h2>
   <p>You can also install Bootstrap using <a href="https://www.npmjs.com">npm</a>:</p>
-  {% highlight bash %}$ npm install bootstrap{% endhighlight %}
+  {% highlight bash %}$ npm install bootstrap@3{% endhighlight %}
   <p><code>require('bootstrap')</code> will load all of Bootstrap's jQuery plugins onto the jQuery object. The <code>bootstrap</code> module itself does not export anything. You can manually load Bootstrap's jQuery plugins individually by loading the <code>/js/*.js</code> files under the package's top-level directory.</p>
   <p>Bootstrap's <code>package.json</code> contains some additional metadata under the following keys:</p>
   <ul>