clarify some docs, improve layout

docs/index.html

@@ -27,14 +27,32 @@ title: Bootstrap · The world's most popular mobile-first and responsive f
     <div class="row">
       <div class="col-sm-4">
         <h4>Package managers</h4>
+        <p>Bootstrap is available via Bower, Composer, Meteor, and npm.</p>
+{% highlight bash %}
+$ npm install bootstrap
+$ bower install bootstrap
+$ meteor add twbs:bootstrap
+$ composer require twbs/bootstrap
+{% endhighlight %}
       </div>
       <div class="col-sm-4">
         <h4>Download from GitHub</h4>
+        <p>You can also <a href="{{ site.repo }}">download the source files</a> from GitHub where our code, issue tracker, and more are hosted.</p>
       </div>
       <div class="col-sm-4">
         <h4>Bootstrap CDN</h4>
+        <p>Quickly include Bootstrap into a project with the Bootstrap CDN, a free service provided by the MaxCDN folks. Just copy and paste the CSS and JS as needed.</p>
+{% highlight html %}
+<link rel="stylesheet" href="{{ site.cdn.css }}">
+<script src="{{ site.cdn.js }}"></script>
+{% endhighlight %}
       </div>
     </div>
+
+    <hr class="half-rule">
+
+    <p class="lead">More customized builds of Bootstrap's CSS and JS are also available.</p>
+    <a href="{{ site.baseurl }}/getting-started/download" class="btn btn-outline btn-lg">More download options</a>
   </div>
 </div>