Moved a test to new test class GetAddressesTest
Moved another two tests to GetAddressesTest
Moved a test to new test class GetPaymentPlanParamsTest
Moved another test to GetPaymentPlanParamsTest
Moved two tests to new test class PaymentPlanPricePerMonthTest
Moved and renamed the class CardPaymentTest
Moved a test to the new test class CloseOrderTest
Moved a test to the new class DeliverInvoiceTest
Deleted a duplicated test
Deleted an unused help function
Deleted another unused function
Moved and renamed the class InvoicePaymentTest
Moved the folder GetPaymentPlanParams
Moved four tests of invoices
Moved and renamed the class PaymentPlanPaymentTest
Made all test methods public
Deleted some outcommented lines
Formatted whitespace
Replaced }  else -> } else
Formatted more whitespace