chore: add migration guide link to homepage

Closes angular-ui#5037

Author: Foxandxss

misc/demo/index.html

@@ -179,6 +179,9 @@ <h3>Installation</h3>
                        <pre><code>angular.module('myModule', ['ui.bootstrap']);</code></pre>
                     </p>
                     <p>You can fork one of the plunkers from this page to see a working example of what is described here.</p>
+                    <h3>Migration to prefixes</h3>
+                    <p>Since version 0.14.0 we started to prefix all our components. If you are upgrading from ui-bootstrap 0.13.4 or earlier,
+                    check our <a href="https://github.com/angular-ui/bootstrap/wiki/Migration-guide-for-prefixes">migration guide</a>.</p>
                     <h3>CSS</h3>
                     <p>Original Bootstrap's CSS depends on empty <code>href</code> attributes to style cursors for several components (pagination, tabs etc.).
                     But in AngularJS adding empty <code>href</code> attributes to link tags will cause unwanted route changes. This is why we need to remove empty <code>href</code> attributes from directive templates and as a result styling is not applied correctly. The remedy is simple, just add the following styling to your application: <pre><code>.nav, .pagination, .carousel, .panel-title a { cursor: pointer; }</code></pre>