Bug 4162 - Followup: only count potential barcodes

Bug 4162 - Followup: only count potential barcodes

The $lines_read++; was before the code which skipped empty
lines. By moving it after the next unless $barcode; code, the
$lines_read variable only counts potential barcodes, and does
not include empty lines.

TEST PLAN
---------
1) Apply patch.
2) Attempt a valid barcode file with empty lines.
   -- The potential barcode count should exclude the empty lines.

Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Empty lines are now no longer counted as potential barcodes.
Passes tests and QA script.

Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>