Load Benefit Cards

Load money onto a batch of benefit cards. Provide a list of cards and individual amounts to be loaded onto each card. If all pre-conditions are fulfilled, then the request is accepted and processed asynchronously. Listen for appropriate CARD_BALANCE_UPDATED callbacks. If any of the pre-conditions is not fulfilled, the request will be rejected immediately. All cards have to be eligible for card loading, i.e. they are active benefit cards and belong to the same organization. There has to be enough money on the organization's card-account. All requested amounts must be positive and specified in the card-account's currency.