Fix bug #12910775 Settings crash after tap on Access Point Names under Mobile networks

- ApnSettings is now a fragment so introduce a new ApnSettingsActivity
- ApsSettingsActivity will use the ApnSettings fragment
- move the getListView() call to onActivityCreated(...) as the ListView
needs to be created before this call can be done.
- add also an alias for the old activity name ".ApsSettings"

Change-Id: Id228722d7f34415d4b036282f0845e28546111df

src/com/android/settings/SettingsActivity.java

@@ -278,7 +278,8 @@ public class SettingsActivity extends Activity
             PaymentSettings.class.getName(),
             KeyboardLayoutPickerFragment.class.getName(),
             ChooseAccountFragment.class.getName(),
-            DashboardSummary.class.getName()
+            DashboardSummary.class.getName(),
+            ApnSettings.class.getName()
     };
 
     private SharedPreferences mDevelopmentPreferences;