message: merchant payment request page currency improvements
  display non-SPEND, non-USD currencies
  round amounts invalid for currency
diff: <div class="merchant-payment-request-page">
  <CardPay::MerchantPaymentRequestHeader/>
  <CardPay::MerchantPaymentRequestCard
  - @amount={{this.displayedAmounts.SPD}}
  - @usdAmount={{this.displayedAmounts.USD}}
  + @amount={{this.cleanedAmounts.displayed.amount}}
  + @secondaryAmount={{this.cleanedAmounts.displayed.secondaryAmount}}
  @merchant={{this.merchantInfo}}
  @merchantAddress={{@model.merchantSafe.address}}
  @paymentURL={{this.paymentURL}}
  