Add LeanCore Extracted Badge (#17)

Add LeanCore Extracted Badge

Author: cpojer

README.md

@@ -1,6 +1,6 @@
 # `@react-native-community/segmented-control`
 
-![CircleCI branch](https://img.shields.io/circleci/project/github/react-native-community/react-native-segmented-control/master.svg) ![npm](https://img.shields.io/npm/v/@react-native-community/segmented-control.svg)
+![CircleCI branch][circle-ci-badge] ![npm][npm-badge] [![Lean Core Extracted][lean-core-badge]][lean-core-issue]
 
 React Native SegmentedControlIOS library. Use SegmentedControlIOS to render a UISegmentedControl iOS.
 
@@ -108,3 +108,8 @@ Please see the [`contributing guide`](/CONTRIBUTING.md).
 ## License
 
 The library is released under the MIT licence. For more information see [`LICENSE`](/LICENSE).
+
+[circle-ci-badge]:https://img.shields.io/circleci/project/github/react-native-community/react-native-segmented-control/master.svg?style=flat-square
+[npm-badge]:https://img.shields.io/npm/v/@react-native-community/segmented-control.svg?style=flat-square
+[lean-core-badge]: https://img.shields.io/badge/Lean%20Core-Extracted-brightgreen.svg?style=flat-square
+[lean-core-issue]: https://github.com/facebook/react-native/issues/23313