initialize method

Implementation

@override
Future<TransactionMonitor> initialize(String masterKey, String pinkey) async {
  Map<String, String> args = {"masterKey": masterKey, "pinkey": pinkey};
  var result = await methodChannel.invokeMethod("initialize", args);
  print("plugin initialize");
  print(result);
  return transactionMonitorFromJson(jsonEncode(result));
}