QHttpServer improvement:

A common use case in the APIs in the modifying methods is to return created/updated value and an HTTP status code 2XX which is not 200 (e.g. Created).

It would be much easier for the user to return a `QHttpServerResponse` both with value and status code instead of using `QHttpServerResponder` or specifying `mimeType` in the `QHttpServerResponse`

e.g.

return QHttpServerResponse(data, QHttpServerResponder::StatusCode::Created);

Add Status code to those methods (defaults to `StatusCode::Ok`):

 QHttpServerResponse(const QJsonArray &data)
 QHttpServerResponse(const QJsonObject &data)
 QHttpServerResponse(QByteArray &&data)
 QHttpServerResponse(const QByteArray &data)
 QHttpServerResponse(const QString &data)
 QHttpServerResponse(const char *data)