Add translations for more payment method strings returned by API

[norbertschuler]

@jmiridis wrote: We will keep these keys but new keys have to be supported. Here the complete list:

tree-cash
tree-donation
restoration-donation (= tree-donation)
conservation-donation
funds-donation
tree-gift
restoration-gift (= tree-gift)
conservation-gift
funds-gift
bouquet-trees-donation
bouquet-restoration-donation
bouquet-conservation-donation
bouquet-funds-donation