Queue print labels for an entire family

[dcs619]

Rock v4 will support label ordering, so the Confirmation page should queue print labels per family then send it all at once to the printer. There's still a possibility (under heavy load) that one kid's labels could end up on another family's sheet but unlikely.

[dcs619]

Closed in latest.

[dcs619]

There is a queue set up during the Print section, but when Print Individual Labels is turned on, the queue only exists of one label at a time. Related to #128 and should be worked on together