add JavaScript ES module version as es

[taisukef]

very easy to use

import { QR } from "https://taisukef.github.io/qrcode-generator/es/QR.js";

const data = QR.encode("Hi!");
console.log(data);

also runs on Deno runtime

$ deno run sample.js

[ralyodio]

Can we merge this in?

[ralyodio]

How would I put the data on a image data url?