Docs: Adding disk space increase to home page

Bug: 18683063
Change-Id: I55f6add27b1ef0382a3038c49c9b42c3c5bd215e
diff --git a/src/index.jd b/src/index.jd
index 4911da7..a8e1338 100644
--- a/src/index.jd
+++ b/src/index.jd
@@ -42,6 +42,14 @@
     <div class="col-8">
     <h3>What's New</h3>
 
+<a href="{@docRoot}source/building.html">
+        <h4>Disk size requirements increased</h4></a>
+        <p>The amount of free disk space listed as required on <strong><a
+	href="{@docRoot}source/building.html">Downloading and
+        Building</a></strong> has been increased significantly.</p>
+
+<img border="0" src="images/Android_Robot_100.png" alt="Android Partner icon" style="display:inline;float:right;margin:5px 10px">
+
 <a href="{@docRoot}source/build-numbers.html">
         <h4>Supported devices and version strings updated</h4></a>
         <p>The list of <strong><a
@@ -50,8 +58,6 @@
         href="{@docRoot}compatibility/5.0/versions.html">version
         strings</a></strong> for Android 5.0 have been updated.</p>
 
-<img border="0" src="images/Android_Robot_100.png" alt="Android Partner icon" style="display:inline;float:right;margin:5px 10px">
-
 <a href="{@docRoot}compatibility/downloads.html">
         <h4>New CTS media files available for download</h4></a>
 	<p>Find <strong><a
@@ -66,17 +72,6 @@
 	href="https://support.google.com/googleplay/contact/brand_developer">Partner
         Brand Inquiry Form</a></strong> for answers to branding questions and review
         of marketing materials.</p>
-
-<a href="{@docRoot}devices/audio/index.html">
-        <h4>Audio gains attributes, USB, latency, and headset documentation</h4></a>
-        <p>The <strong><a
-        href="{@docRoot}devices/audio/index.html">Audio section</a></strong> now describes <strong><a
-	href="{@docRoot}devices/audio/attributes.html">Attributes</a></strong>, <strong><a
-        href="{@docRoot}devices/audio/usb.html">USB digital audio</a></strong> support, and <strong><a
-        href="{@docRoot}devices/audio/funplug.html">latency tools</a></strong>, while a <strong><a
-	href="{@docRoot}accessories/headset-spec.html">Wired audio headset
-        specification</a></strong> can now be found in the <strong><a
-        href="{@docRoot}accessories/index.html">Accessories section</a></strong>.</p>
     </div>
 
     <div class="col-8">
diff --git a/src/source/building.jd b/src/source/building.jd
index bf5ce92..bd929bd 100644
--- a/src/source/building.jd
+++ b/src/source/building.jd
@@ -37,7 +37,8 @@
   </li>
 
   <li>At least 50GB of free disk space for a checkout, 100GB for a single
-build, and 150GB or more for multiple builds.</p>
+  build, and 150GB or more for multiple builds. If you employ ccache, you will
+  need even more space.</p>
   </li>
 
   <li>