Adding the dispatcher

Next off we need a dispatcher that is able to take our message, like so:

// demo/dispatcher.js

class Dispatcher {
  constructor() {
    this.listeners = [];
  }

  dispatch(message) {
    this.listeners.forEach(listener => listener(message));
  }

  register(listener) {
    this.listeners.push(listener);
  }
}

const dispatcher = new Dispatcher();
export default dispatcher;