initial commit
Quantity of ticket windows can be set for shop
CashBox object
Shop contains list of cash box
Cash box factory
Shop uses factory for cash box's creation
Customers that have products count
Simple cash box choose factory that always chooses first cash box in list
Customer has choose strategy
Shop can simulate steps of customer service
Cash box can place customers in queue
Customers are placed in cash box in each steps
Simulation tests are moved to separate test class
Cash box can serve customer
Should not decrease products less zero
Remove customer from cash box if served