feat: HTTP Header React Component

[aheissenberger]

Add a Component <HttpHeader name="Cache-Control" value="max-age=3600" /> which allows to set a HTTP header from a React Component.

Example:

import { HttpHeader } from "waku/utils";

export default function About(props) {
  return (
    <>
      <HttpHeader name="Cache-Control" value="max-age=3600" />
        <h1>About</h1>
    </>
  );
}

[dai-shi]

I'll be working on #329 related to this.
However, is too tricky & too hard to implement. So, it won't be like that. Only what React supports will be supported.

You could change the default headers with config.htmlHead for now.