v1.0.0 released

Use jsx runtime instead of React. And drop React v0.14.0 support.
according to here. https://reactjs.org/blog/2020/09/22/introducing-the-new-jsx-transform.html

// Inserted by a compiler (don't import it yourself!)
import {jsx as _jsx} from 'react/jsx-runtime';

function App() {
  return _jsx('h1', { children: 'Hello world' });
}