Add docs for discount utils functions
Add docs for discount utils functions

UITools/saleor,UITools/saleor,maferelo/saleor,mociepka/saleor,maferelo/saleor,UITools/saleor,UITools/saleor,UITools/saleor,mociepka/saleor,maferelo/saleor,mociepka/saleor