Move Android Keystore impl to android.security.keystore.

This moves the non-public API classes backing Android Keystore from
android.security to android.security.keystore, a package specially
created for Android Keystore.

Bug: 18088752
Change-Id: Ibf04d6a26c54d310b0501fc5e34f37b1176324ad

keystore/java/android/security/GateKeeper.java

@@ -1,3 +1,19 @@
+/*
+ * Copyright (C) 2015 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.
+ */
+
 package android.security;
 
 import android.os.RemoteException;