PGPSignatureSubpacketGenerator.addEmbeddedSignature(boolean, PGPSignature)
PGPSignatureSubpacketGenerator.addIntendedRecipientFingerprint(boolean, PGPPublicKey)
PGPSignatureSubpacketGenerator.addNotationData(boolean, boolean, String, String)
PGPSignatureSubpacketGenerator.addRevocationKey(boolean, int, byte[])
PGPSignatureSubpacketGenerator.addSignerUserID(boolean, String)