Export: Refactor interfaces and classes

Elwig/Helpers/Export/Ebics.cs

@@ -1,14 +1,26 @@
-using Elwig.Models;
+using Elwig.Helpers.Billing;
 using System;
 using System.Collections.Generic;
 using System.Threading.Tasks;
 
 namespace Elwig.Helpers.Export {
-    public class Ebics : IBankingProvider {
+    public class Ebics : IBankingExporter {
 
-        public string FileExtension => "xml";
+        public static string FileExtension => "xml";
 
-        public Task Export(string filename, int avnr, IEnumerable<Member> members) {
+        public void Dispose() {
+            throw new NotImplementedException();
+        }
+
+        public ValueTask DisposeAsync() {
+            throw new NotImplementedException();
+        }
+
+        public void Export(IEnumerable<Transaction> data) {
+            throw new NotImplementedException();
+        }
+
+        public Task ExportAsync(IEnumerable<Transaction> data) {
             throw new NotImplementedException();
         }
     }