Comment 1 for bug 1721610

Working branch user/jeffdavis/lp1721610-user-barcode-completion has a fix:

http://git.evergreen-ils.org/?p=working/Evergreen.git;a=commitdiff;h=070debec

For simplicity, I've just reused the barcode choice modal template from bug 1699566.

This fix only applies to the Check Out Items screen. I'm not sure if there are other parts of the web client where we need to handle multiple matching patron barcodes.