NewError creates new custom handler error.

WrapError creates new wrapped handler error.

Account define account description.

AccountRequest define request to create new account.

Error define custom handler error.

Payment define payment description.

PaymentRequest define request to create new payment.

ServerStatusResponse declare response for status request.

AccountBuilder declare interface to build new account.

AccountFactory declare interface to access accounts and payments information (kind of facade to simplify interface).

PaymentBuilder declare interface to build new payment.

ErrorKind define kind of error, occurred.