docs: fix urls on homepage for offline docs

Change-Id: Ifa1da094ee6482c7324ec5a8b50d245d505390b9

docs/html/index.jd

@@ -14,7 +14,7 @@ page.metaDescription=The official site for Android developers. Provides the Andr
  <ul>
  <li class="item carousel-home">
  <div class="content-left col-9">
- <a href="/about/versions/jelly-bean.html"><img src="/images/home/android-jellybean.png" ></a>
+ <a href="{@docRoot}about/versions/jelly-bean.html"><img src="{@docRoot}images/home/android-jellybean.png" ></a>
  </div>
  <div class="content-right col-6">
  <h1>Jelly Bean now available!</h1>
@@ -23,7 +23,7 @@ page.metaDescription=The official site for Android developers. Provides the Andr
  <p>New APIs are also available that allow you to build richer and more
  interactive notifications, transfer larger
  payloads through NFC, discover services over Wi-Fi, and much more.</p>
- <p><a href="/about/versions/jelly-bean.html" class="button">More 
+ <p><a href="{@docRoot}about/versions/jelly-bean.html" class="button">More 
  about Jelly Bean</a></p>
  </div>
  </li>
@@ -35,12 +35,12 @@ page.metaDescription=The official site for Android developers. Provides the Andr
  <h1>Make your Android apps<br>look great</h1>
  <p>New templates in the design guide make it easier than ever to design apps
 that are beautiful and easy to use.</p>
- <p><a href="/design/index.html" class="button">Learn More</a></p>
+ <p><a href="{@docRoot}design/index.html" class="button">Learn More</a></p>
  </div>
  </li>
  <li class="item carousel-home">
  <div class="content-left col-10">
- <img src="/images/home/google-io.png">
+ <img src="{@docRoot}images/home/google-io.png">
  </div>
  <div class="content-right col-5">
  <h1>Watch Android at <br/>Google I/O!</h1>
@@ -52,7 +52,7 @@ class="button">See the Android Sessions</a></p>
  </li>
  <li class="item carousel-home">
  <div class="content-left col-10">
- <img src="/images/home/google-play.png"
+ <img src="{@docRoot}images/home/google-play.png"
  style="margin-top:50px">
  </div>
  <div class="content-right col-5">