New version update notification

Notify user when a new version of browser is available internally.

Change-Id: I29ae1443c473781c3227a574ee42eb5f7e1be36c
diff --git a/res/xml/about_preferences.xml b/res/xml/about_preferences.xml
index 2b156fa..e1a5e86 100644
--- a/res/xml/about_preferences.xml
+++ b/res/xml/about_preferences.xml
@@ -62,4 +62,8 @@
         android:title="@string/swe_legal"
         android:summary="@string/swe_pref_legal_info_summary"/>
 
+    <Preference
+        android:key="update_notification"
+        android:title="@string/update" />
+
 </PreferenceScreen>