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

src/com/android/settings/SettingsPreferenceFragment.java

@@ -24,7 +24,6 @@ import android.content.ContentResolver;
 import android.content.Context;
 import android.content.DialogInterface;
 import android.content.pm.PackageManager;
-import android.graphics.drawable.Drawable;
 import android.os.Bundle;
 import android.support.v7.preference.Preference;
 import android.support.v7.preference.PreferenceGroup;
@@ -187,6 +186,11 @@ public abstract class SettingsPreferenceFragment extends InstrumentedPreferenceF
         setEmptyView(loading);
     }
 
+    public void setLoading(boolean loading, boolean animate) {
+        View loading_container = getView().findViewById(R.id.loading_container);
+        Utils.handleLoadingContainer(loading_container, getListView(), !loading, animate);
+    }
+
     public void registerObserverIfNeeded() {
         if (!mIsDataSetObserverRegistered) {
             if (mCurrentRootAdapter != null) {