Remove license from README

Remove the wrong license information (pasted below) from the readme file

_License
Copyright 2018 Google, Inc.

All image and audio files (including *.png, *.jpg, *.svg, *.mp3, *.wav and *.ogg) are licensed under the CC BY 4.0 license. All other files are licensed under the Apache 2 license.

Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the LICENSE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you 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._

Ouvrez le README du dépôt et repérez la section de licence collée qui commence par « License » et « Copyright 2018 Google, Inc. ». Supprimez ce bloc incorrect, puis examinez le README rendu et le diff pour confirmer que le reste de la documentation est inchangé.

Rédigé par le modèle d'indexation à partir du texte de l'issue.