Add `--help` flag to `react-scripts`

Created by: ocavue

This PR use commander (which is already used by create-react-app CLI) to provide a beautify CLI interface.

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please provide us with clear instructions on how you verified your changes work.

Before this PR:

$ yarn run react-scripts --help                                                                                                                                                                                                                                              
yarn run v1.19.2
$ /Users/ocavue/code/github/rino/node_modules/.bin/react-scripts --help
Unknown script "--help".
Perhaps you need to update react-scripts?
See: https://facebook.github.io/create-react-app/docs/updating-to-new-releases

After this PR:

$ yarn run react-scripts --help    
Usage: react-scripts [options] [command]

Options:
  -V, --version    output the version number
  -h, --help       output usage information

Commands:
  start [options]  Runs the app in the development mode.
  build            Builds the app for production to the `build` folder.
  test             Launches the test runner in the interactive watch mode.
  eject            Eject config.

$ yarn run react-scripts start -h
Usage: react-scripts start [options]

Runs the app in the development mode.

Options:
  --port <port>  Specify port (default: 3000)
  --host <host>  Specify host (default: "0.0.0.0")
  --https        Use https
  -h, --help     output usage information