Add Wifi Setup screen for Setup Wizard with XL size screen.

* Add WifiSettingsForSetupWizardXL as a new Activity
The activity has WifiSettings fragment in it. It also contains
several buttons, texts around the fragment.

* Making configuration UI part of Preference list.
In Wifi Setup for Setup Wizard XL, WifiSettings fragment lets
a UI for configuring access points shown inside a
PregerenceCategory object, while it has been shown as Dialog.

To achieve this action, WifiDialog is decomposed into two parts:
- WifiConfigUiBase (Mainly UI part)
- WifiConfigController (Mainly Wifi controller part)

All codes for wifi configuration in WifiDialog is now in
WifiConfigController, which is reused from
WifiConfigPreference.

* Misc stuff
- Remove AccessPoint#compareTo(). Instead,
  AccessPoint.AccessPointComparater should be used when needed.

Change-Id: I520d690d3301837d32f91dad54a973a379ce1989

src/com/android/settings/wifi/Summary.java

@@ -16,11 +16,10 @@
 
 package com.android.settings.wifi;
 
-import com.android.settings.R;
-
 import android.content.Context;
 import android.net.NetworkInfo.DetailedState;
-import android.text.TextUtils;
+
+import com.android.settings.R;
 
 class Summary {
     static String get(Context context, String ssid, DetailedState state) {