am 9b822b96: docs: Added link to CarExtender class from Auto Getting Started doc.

</li>

<li><strong><a href="{@docRoot}tools/support-library/setup.html">Install the

support library</a></strong> - If you are building messaging apps for Auto, you

need the {@code NotificationCompat.CarExtender} class contained in the

need the {@link android.support.v4.app.NotificationCompat.CarExtender} class

contained in the

<a href="{@docRoot}tools/support-library/features.html#v4">v4 support library</a>.

This class allows you to create notifications that are compatible with Auto

devices.</li>