add support for CRUD Customers to disk

uses serialization to binary files.
fix Customer constructor
fix Customer and Sale constructor (its ok now)
fix CustomerEntity constructor
add DataAccess SaleController
add abstract DataController
make dataControllers throw ex on save fail
fix CRUD for Sale in DataAccessFacade
fix assignment of IEntity props when rebuilding
fix SaleEntity serializable
fix DeleteSale in ModelFacade
implement interfaces as DataAccess entities
move DataController into Controllers
PaymentController filname Payments.bin

I have written Payment controller in DataAccessLayer which is a 100%
copy of saleController being salecontroller is of Isale and sale Entity
type and payment controller is of Ipayment and paymentEntity type.
SupplierController and csproj
DataAccess

DataAccess: PaymentContractController, PaymentController &
PaymentRuleController.
BookingController and PaymentRuleCatalogController

Tror de er fine nok
add comments
Merge remote-tracking branch 'origin/DataAccessEntityCecilie' into DataAccessEntity
Merge remote-tracking branch 'origin/DataAccessEntityImp' into DataAccessEntity