Basic implementation.
ReceiptPrinter has a main method for testing.
ReceiptPrinterTest also provides minimal JUnit test campaign.

ReceiptPrinter uses SalesTaxesStrategy to apply texes policy.
RoundPolicy has been decoupled from tax policy and it's provided as
RoundPolicyStrategy.

Basic example uses RoundSalesTaxesStrategy as SalesTaxes strategy and
RoundToHigher5Policy as RoundPolicy strategy.