Merge pull request #5216

5ec654b [Qt] update paymentserver license and cleanup ordering (Philip Kaufmann)
4333e26 [Qt] add BIP70 DoS protection test (Philip Kaufmann)
31f8494 [Qt] add BIP70 payment request size DoS protection for URIs (Philip Kaufmann)
2284ccb [Qt] remove dup lock that is done in SetAddressBook() (Philip Kaufmann)
1ec753f [Qt] ensure socket is set to NULL in PaymentServer::ipcSendCommandLine (Philip Kaufmann)
814429d [Qt] add BIP70/BIP71 constants for all messages and mime types (Philip Kaufmann)
b82695b [Qt] make PaymentServer::ipcParseCommandLine void (Philip Kaufmann)