added qr scan support for cameras/mobile devices

almost working - need to flip the camera
used this:
https://github.com/RagnarDanneskjold/html5qrcodereader

also LINE 18 change - already patched upstream:
<script src="./static/js/bootstrap.js"></script>
 change to
<script src="./static/js/bootstrap.min.js"></script>

bkchaind FTW