Fixed odd receipt screendisplay bug with upcs that began with 002.

For some creason the screendisplay view was showing the regPrice as
opposed to the unitPrice for all upcs that began with 002. That was
causing an issue at the register for items that began with 002 that were
on sale.

Example:
 - Lara bar (begins with 002) with regPrice of $1.69 and sale price of
   $1 is rung up at the register
 - IS4C was showing that 1@1.69 lara bars were rung up. But the total
   was correct: $1. Instead, IS4c should have displayed the quantity as
   1@1