Add new bank statement flows to support PGP encryption

Added the following bank statement flows to support PGP encryption:

• SyncBai2BankStatementData_PGP
• SyncMT940BankStatementData_PGP
• SyncMT942BankStatementData_PGP

PGP stands for Pretty Good Privacy which is a data encryption and decryption computer program that provides cryptographic privacy and authentication for data communication.

PGP is often used for signing, encrypting and decrypting texts, e-mails, files, directories and whole disk partitions to increase the security of e-mail communications. PGP and similar products follow the OpenPGP standard (RFC 4880) for encrypting and decrypting data.