Update data usage UX

Update the UX and dig the data usage screen out of a huge whole of
technical debt.  Switch every to use Preferences rather than standard
layouts and ListViews.

Split data usage into several fragments, all separated.

DataUsageSummary:
 - Shows a summary of the 'default' usage at the top, this will be
   the default sim on phones, or wifi if it has it, or ethernet
   as last attempt to show something.
 - Also has individual categories for each network type that has
   data, cell, wifi, and ethernet. Maybe should look into bt though?

DataUsageList:
- Takes a NetworkTemplate as an input, and can only be reached from
  the network specific categories in DataUsageSummary
- Shows a graph of current usage for that network and links to
  app detail page for any app.
- Has gear link to quick get to billing cycle screen if available

BillingCycleSettings:
 - Just a screen with the cycle day and warning/limits separated
   out from the data usage.

AppDataUsage:
 - App specific data usage details
 - May need some UX iteration given lack of clarity in the spec

Bug: 22459566
Change-Id: I0222d8d7ea7b75a9775207a6026ebbdcce8f5e46

res/xml/app_memory_settings.xml

@@ -18,11 +18,15 @@
                   android:title="@string/memory_usage">
 
     <PreferenceCategory
-        android:title="@string/average_memory_use" />
+        android:title="@string/average_memory_use"
+        android:layout="@layout/preference_category_short" />
 
-    <com.android.settings.applications.LayoutPreference
+    <com.android.settings.SummaryPreference
         android:key="status_header"
-        android:layout="@layout/proc_stats_ui" />
+        android:selectable="false" />
+
+    <com.android.settings.applications.SpacePreference
+        android:layout_height="5dp" />
 
     <Preference
         android:key="frequency"