Added address validity check

ref #105

src/models/actions/create/CreateDonor.ts

@@ -29,7 +29,7 @@ export class CreateDonor extends CreateParticipant {
         newDonor.receiptNeeded = this.receiptNeeded;
         newDonor.address = this.address;
 
-        if (this.receiptNeeded == true && this.address == null) {
+        if (this.receiptNeeded == true && this.address.isValidAddress == false) {
             throw new DonorReceiptAddressNeededError()
         }