payment.js
//
// data will contain the following details for each field:
// - empty: boolean
// - field: string
// - length: number
// - potentiallyValid: boolean
// - touched: boolean
// - valid: boolean
//
// the card field object will also contain the following:
// - brand: string
// - brandNiceType: string
//
// the cvv field object will also contain the following:
// - maxLength: number
//
paymentForm.getState((data) => {
});