Update index.php

Fixed Issue about the QR code
In the pay-now-button-v2.js it does already the qr code for you all you need is the class named "qr-code". fFr a more customized qr url with label and amount, I suggest you customize your own "pay-now-button-v2.js". As explained in blockchain#7

Please clone https://github.com/colinkelly/receive_payment_php_demo.git for an up an running "out of the box" demo