PrinterMain: Add default value for LasersList.
PrinterMain: Add default value for LasersList.

johnkingsley/aprinter,ambrop72/aprinter,johnkingsley/aprinter,fixator/aprinter,fixator/aprinter,ambrop72/aprinter,fixator/aprinter,ambrop72/aprinter,ambrop72/aprinter,fixator/aprinter,ambrop72/aprinter,johnkingsley/aprinter,johnkingsley/aprinter,fixator/aprinter,ambrop72/aprinter,johnkingsley/aprinter,fixator/aprinter,johnkingsley/aprinter,ambrop72/aprinter,johnkingsley/aprinter