VolumeZen: Sound & Notifications settings.

- Add sound settings under the newly combined Sound & Notifications
  top-level settings page.
- New slider preferences for setting audio stream volumes.
- Migrate checkbox prefs to switch prefs.
- New settings subpage for touch sounds.
- New settings subpage for "Showing notifications"
- New setting pref for displaying intercepted notifications in zen mode.
- New tri-state lockscreen notifications pref.
- Add priority + sensitivity options to app notification dialog.
- Remove badges on app notifications row, migrate to subtitle text.
- Migrate strings to common spot in strings.xml
- Remove heads up setting.
- Remove tweaks category (unused).
- Clean up notification settings, separate out into a code section per option.
- Clean up _settings.xml files, prefix each pref with option name.
- Add appropriate indexing data to each settings page.

Depends on f/b change Ic30aa575ae07650cee62c8c1d83b6bc69395cf0d

Change-Id: If700385a7d0057f6c4c4bcf6e648dcf88b8ebff2
diff --git a/res/layout/notification_app_dialog.xml b/res/layout/notification_app_dialog.xml
index a8f7880..5b2fd1a 100644
--- a/res/layout/notification_app_dialog.xml
+++ b/res/layout/notification_app_dialog.xml
@@ -44,4 +44,22 @@
         android:text="@string/app_notifications_dialog_show"
         android:textAppearance="?android:attr/textAppearanceListItem" />
 
+    <CheckBox
+        android:id="@android:id/button2"
+        android:layout_width="match_parent"
+        android:layout_height="@dimen/notification_app_icon_size"
+        android:layout_below="@android:id/button1"
+        android:layout_marginStart="@dimen/content_margin_left"
+        android:text="@string/app_notifications_dialog_priority"
+        android:textAppearance="?android:attr/textAppearanceListItem" />
+
+    <CheckBox
+        android:id="@android:id/button3"
+        android:layout_width="match_parent"
+        android:layout_height="@dimen/notification_app_icon_size"
+        android:layout_below="@android:id/button2"
+        android:layout_marginStart="@dimen/content_margin_left"
+        android:text="@string/app_notifications_dialog_visibility"
+        android:textAppearance="?android:attr/textAppearanceListItem" />
+
 </RelativeLayout>
\ No newline at end of file