docs: add whitelisting instructions and new index icons

Change-Id: If720e2a5c3cae1d5cceff397d06001e551443fce
diff --git a/docs/html/index.jd b/docs/html/index.jd
index 2177352..01d4e7b 100644
--- a/docs/html/index.jd
+++ b/docs/html/index.jd
@@ -71,7 +71,7 @@
           data-sortorder="" data-cardsizes="6x6, 6x6, 6x6" data-maxresults="3"></div>-->
 
           <div class="col-3-wide">
-            <img src="" alt="">
+            <img src="/images/home/wear.png">
 
             <p>Wearable</p>
             <p class="landing-small">
@@ -83,7 +83,7 @@
           </div>
 
           <div class="col-3-wide">
-            <img src="" alt="">
+            <img src="/images/home/tv.png">
 
             <p>TV</p>
             <p class="landing-small">
@@ -95,7 +95,7 @@
           </div>
 
           <div class="col-3-wide">
-            <img src="" alt="">
+            <img src="/images/home/auto.png">
 
             <p>Auto</p>
             <p class="landing-small">