SavedCard.fromJson constructor
Implementation
SavedCard.fromJson(Map<String, dynamic> jsonMap){
nameOnCard = jsonMap['nameOnCard'];
firstSixDigits = jsonMap['first6Digits'];
lastFourDigits = jsonMap['last4Digits'];
expiryMonth = jsonMap['expiryMonth'];
expiryYear = jsonMap['expiryYear'];
payModeId = jsonMap['payModeId'];
}