QR Code library update/bugfix

Hey there,

I've recently identified and fixed a bug in my QR Code library that could cause unreadable codes under certain conditions. I went all the way and ported the fix even to the outdated branches, that includes the one your libary is using. The fixed version is now available as 1.0.9. I'd also advise to use a version switch in your composer.json like so "chillerlan/php-qrcode": "1.0.9 || ^2.0 || ^3.2 || ^4.0" to allow more modern versions if the underlying PHP version is supported. The API may have changed slightly between the different versions, but since your library only uses the most basic syntax, it remains unaffected.

Cheers!