Does Article 56 EC (now Article 63 TFEU) mean that an investment fund established outside the Netherlands cannot be refused, on the ground that it is not subject to an obligation to withhold Netherlands dividend tax, a refund of Netherlands dividend tax which was withheld on dividends which that investment fund received from corporate bodies established in the Netherlands, whereas such a refund is granted to a fiscal investment institution established in the Netherlands, which, subject to the withholding of Netherlands dividend tax, distributes the proceeds of its investments to its shareholders or participants on an annual basis?