removed appkey and gateway url reference from Xamarin iOS
removed appkey and gateway url reference from Xamarin iOS

shrishrirang/azure-mobile-apps-quickstarts,shrishrirang/azure-mobile-apps-quickstarts,lindydonna/azure-mobile-apps-quickstarts,shrishrirang/azure-mobile-apps-quickstarts,Azure/azure-mobile-apps-quickstarts,lindydonna/azure-mobile-apps-quickstarts,Azure/azure-mobile-apps-quickstarts,shrishrirang/azure-mobile-apps-quickstarts,lindydonna/azure-mobile-apps-quickstarts,Azure/azure-mobile-apps-quickstarts,Azure/azure-mobile-apps-quickstarts,shrishrirang/azure-mobile-apps-quickstarts,Azure/azure-mobile-apps-quickstarts,shrishrirang/azure-mobile-apps-quickstarts,lindydonna/azure-mobile-apps-quickstarts,lindydonna/azure-mobile-apps-quickstarts,lindydonna/azure-mobile-apps-quickstarts,Azure/azure-mobile-apps-quickstarts