Re-license update_engine to Apache2

This patch automatically replaced the license on all text files from
Chromium OS (BSD style) to AOSP (Apache2), keeping the original year as
a reference.

The license header was added to .gyp and .gypi files, the NOTICE was
replaced with a copy of the Apache2 license and MODULE_LICENSE_* file
was updated.

BUG=b/23084294
TEST=grep 'Chromium OS Authors' doesn't find anything.

Change-Id: Ie5083750755f5180a8a785b24fe67dbf9195cd10

action_processor.h

diff --git a/action_processor.h b/action_processor.h
index 121e0e1..cd458ad 100644
--- a/action_processor.h
+++ b/action_processor.h
@@ -1,6 +1,18 @@
-// Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
+//
+// Copyright (C) 2011 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.
+//
 
 #ifndef UPDATE_ENGINE_ACTION_PROCESSOR_H_
 #define UPDATE_ENGINE_ACTION_PROCESSOR_H_