styled-components and emotion package

[macintoshhelper]

Create styled-components package wrapper that lets you use components without react-native-web.

This may be necessary for styled-components/primitives SSR support, or for use cases where react-native-web isn't installed.

We should encourage the use of styled-components/primitives instead, in documentation.

This could be a new package like @react-platform/styled

Pseudo-code for the wrapper:

const styled = Platform.select({
  web: () => require('styled-components'),
  default: () => require('styled-components/primitives'),
})();

if (Platform.OS === 'web') {
  styled.View = styled.div;
  styled.Text = styled.span;
  styled.Image = styled.img;
} else {
  styled.div = styled.View;
  styled.img = styled.Image;
  styled.span = styled.Text;
}

module.exports = styled;