May need to update readme and version

[Zihan Chen (MSFT)]

We should expand the README to include how to install this package as @types/react-native:
I believe this works with many NPM package managers:
"@types/react-native": "npm:react-native-tscodegen-types@0.67.0",

Why were the types published as 0.67.0?  Wouldn't it have been better to align with @types/react-native versioning?