Show a hint about credit card fees for international usage

[norbertschuler]

Describe the feature you'd like to see included in Plant-for-the-Planet App. If you donate to a projects where the credit card does not get charged in your local country, you might experience some additional free from your bank for international usage of your card, e.g. in Germany the bank charges 1.50€ for doing a payment in the united states. We should show a hint describing this in every project which might be affected by this or a general hint on the payment pages.

What are the use cases for this feature? Transparent information about additional costs for donations to avoid user complaining about not knowing about this.

Examples of this feature or functionality. If you donate to the Eden project with a German credit card (e.g. Deutsche Bank) you get charged this additional fee of 1.50€ next to the donation of 4€ which you do not know until you get charged (picture below in German):