Move react-native-babel-transformer and react-native-babel-preset fro…

…m Metro to React Native repo (facebook#1024)

Summary:
Pull Request resolved: facebook#1024

X-link: facebook/react-native#38228

Changelog: [General][Changed] - Move react-native-babel-transformer and react-native-babel-preset from Metro to React Native repo.

Metro Changelog:  **[Breaking]** - Remove `metro-react-native-babel-transformer` and `metro-react-native-babel-preset`, to be published as `react-native/metro-babel-transformer` and `react-native/babel-preset` instead.

This diff does the following:
- Move `metro/packages/metro-react-native-babel-preset` to `react-native/packages/react-native-babel-preset`.
- Rename `metro-react-native-babel-preset` package to `react-native/babel-preset`.
- Move `metro/packages/metro-react-native-babel-transformer` to `react-native/packages/react-native-babel-transformer`.
- Rename `metro-react-native-babel-transformer` package to `react-native/metro-babel-transformer`.
- Upadate dependencies.

Reviewed By: robhogan

Differential Revision: D46977466

fbshipit-source-id: af5bf5b3af0e58bf8f8a42769318041059ddfa91

docs/ModuleAPI.md

@@ -41,7 +41,7 @@ Similar to [`module.exports`](https://nodejs.org/api/modules.html#moduleexports)
 We currently recommend the use of [`@babel/plugin-transform-modules-commonjs`](https://babeljs.io/docs/babel-plugin-transform-modules-commonjs) in Metro projects to support `import` and `export`.
 
 :::note
-In React Native projects that use `metro-react-native-babel-preset`, `import` and `export` are supported out of the box.
+In React Native projects that use `@react-native/babel-preset`, `import` and `export` are supported out of the box.
 :::
 
 ## `import()` (dynamic import)