File download rework

[fnkkio]

Detailes: TBA

[Emdek]

@fnkkio, uhm, one thing is for sure, that dialog related part needs own PR, changing order to:

	const QMimeType mimeType(transfer->getMimeType());

	m_ui->nameTextLabelWidget->setText(fileName);
	m_ui->typeTextLabelWidget->setText((mimeType.comment() == QLatin1String("unknown")) ? mimeType.name() : mimeType.comment());