Added functionality to create chat

lib/api/marianumcloud/talk/createRoom/createRoom.dart

@@ -0,0 +1,24 @@
+
+import 'package:http/http.dart' as http;
+import 'package:http/http.dart';
+
+import '../talkApi.dart';
+import 'createRoomParams.dart';
+class CreateRoom extends TalkApi<void> {
+  CreateRoomParams params;
+
+  CreateRoom(this.params) : super("v4/room", params);
+
+  @override
+  assemble(String raw) {
+  }
+
+  @override
+  Future<Response>? request(Uri uri, Object? body, Map<String, String>? headers) {
+    if(body is CreateRoomParams) {
+      return http.post(uri, headers: headers, body: body.toJson().map((key, value) => MapEntry(key, value.toString())));
+    }
+
+    return null;
+  }
+}