snake_case mentioned instead kebab-case in documentation of create-class function.

[monotech-hq]

Tiniest issue in the world, I know. But ... I've just ran into the following lines in the documentation of the 'create-class' function:

"Map keys should use React.Component method names (https://reactjs.org/docs/react-component.html), and can be provided in snake-case or camelCase."

So, that should be 'kebab-case', because 'snake_case' uses underlines, not hyphens.

Sry :D