Added head turn option for Face Unlock.

In security settings there is an option for head turn and it shows the current
status (on/off).  Clicking on this goes to another screen that describes the
feature and allows the user to it on/off.
Since the head turn option goes to a different screen instead of using a check box,
this change also rips out the rest of the code for the old liveliness checkbox.

Change-Id: I197af51084f3e751081fa159dadd6c2c80840d1e

res/layout/biometric_weak_liveliness.xml

@@ -0,0 +1,46 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Copyright (C) 2012 The Android Open Source Project
+
+     Licensed under the Apache License, Version 2.0 (the "License");
+     you may not use this file except in compliance with the License.
+     You may obtain a copy of the License at
+
+          http://www.apache.org/licenses/LICENSE-2.0
+
+     Unless required by applicable law or agreed to in writing, software
+     distributed under the License is distributed on an "AS IS" BASIS,
+     WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+     See the License for the specific language governing permissions and
+     limitations under the License.
+-->
+<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:orientation="vertical"
+    android:paddingLeft="6dip"
+    android:paddingRight="6dip"
+    android:layout_width="match_parent" android:layout_height="wrap_content"
+    android:scrollbars="vertical" >
+
+    <ScrollView
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:fillViewport="true">
+
+        <LinearLayout
+            android:layout_width="match_parent"
+            android:layout_height="wrap_content"
+            android:orientation="vertical">
+
+            <TextView android:id="@+id/biometric_weak_liveliness_explained"
+                android:layout_width="match_parent"
+                android:layout_height="wrap_content"
+                android:layout_marginTop="20dip"
+                android:gravity="top"
+                android:text="@string/biometric_weak_liveliness_explained"
+                android:textAppearance="?android:attr/textAppearanceMedium"
+            />
+        </LinearLayout>
+
+    </ScrollView>
+
+</LinearLayout>
+