README: Add BRJ organisation logo.

Warehouse: Add WarehouseProductStatusInterface

Add getPickupCode and isRealProduct method.

Product: Add depenedency to Brand and Manufacturer.

ProductTag: Add label.

Add ProductTagInterface

PaymentInterface: Add description.

WarehouseManagerInterface: Fix codestyle.

Add CartSale and CartVoucher.

Add CurrencyResolverInterface