Update README.md

Author: 994914624

README.md

@@ -17,3 +17,19 @@ react-native link @sensors.data/react-native-sensors-analytics
 
 
 ### 详细文档请参考：[Android & iOS SDK 在 React Native 中使用说明](https://www.sensorsdata.cn/manual/sdk_reactnative.html)
+
+## License
+
+Copyright 2015－2020 Sensors Data Inc.
+
+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.