Add TypeScript option to create-next-app

[ctjlewis]

Describe the feature you'd like to request

It would be nice to run yarn create next-app-ts or yarn create next-app --ts which would generate a project configured for TS (tsconfig.json, necessary dependencies like types in package.json, etc.)

Describe the solution you'd like

Add either a separate create-next-app-ts package, or add a --ts option to the current create-next-app.

Describe alternatives you've considered

N/A