eps1lon and oliviertassinari [examples] Update create-react-app examples (#13453)
* [examples] Use react-scripts for typescript

* [examples] Update create-react-app examples

Includes basic output when running `yarn create react-app`

* [examples] Add service workers

* [expamples] prettify serviceWorkers

* [examples] Don'l cra serviceWorkers

cra has its own rules anyway

* fix npm run flow
Latest commit 1990d14 Oct 30, 2018