Update README.md

[ThibaultPelloquin]

Adding info about using directly dompdf in Symfony without bundle

[Ayush9054]

<?php
require 'vendor/autoload.php';

use Dompdf\Dompdf;
use Dompdf\Options;

$options = new Options();
$options->set('isHtml5ParserEnabled', true);

$dompdf = new Dompdf($options);


$html = '<p>There is a less-than character after this word < Is it rendered?</p>';
$dompdf->loadHtml($html);

$dompdf->setPaper('A4', 'portrait');

$dompdf->render();

$dompdf->stream();
?>

[Ayush9054]

THAT WAS A DUMMY COMMENT

[bsweeney]

Instead of a change to the README I recommend adding a page to the wiki.