Add Backup/Restore sample to the SDK docs

Part of bug #2545514

Change-Id: I9085ebfdce3552ddab602eec8d40de67b219a834
diff --git a/samples/BackupRestore/_index.html b/samples/BackupRestore/_index.html
new file mode 100755
index 0000000..4ac141c
--- /dev/null
+++ b/samples/BackupRestore/_index.html
@@ -0,0 +1,5 @@
+<p>The Backup/Restore application illustrates a few different approaches that an
+application developer can take when integrating with the Android Backup Manager
+using the <code><a
+href="../../../reference/android/app/backup/BackupAgent.html">BackupAgent</a></code> API
+introduced in Android 2.2.</p>