* Provider code must be required, so barcode could be automatically generated.
* Barcode could not be editable in any way by the user (edit and new views).
* Test.
Comment for future reviews
Fix bad rendering of error message, and fix test to support autogenerated barcodes.
Fix test (day sale) to support auto barcodes
Ups, add the file :P
Fix cancel sale test to acomplish auto barcodes
Fix merge
Merge pull request #14 from suyccom/todo_10501_autogenerate_barcodes

Autogenerated barcodes