Implement Webuntis HTTP Api and Display

lib/api/webuntis/queries/getSubjects/getSubjects.dart

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+import 'dart:convert';
+
+import 'package:marianum_mobile/api/webuntis/webuntisApi.dart';
+
+import '../../apiResponse.dart';
+import 'getSubjectsResponse.dart';
+
+class GetSubjects extends WebuntisApi {
+  GetSubjects() : super("getSubjects", null);
+
+  @override
+  Future<GetSubjectsResponse> run() async {
+    String rawAnswer = await query(this);
+    return finalize(GetSubjectsResponse.fromJson(jsonDecode(rawAnswer)));
+  }
+}