§ 7-a. Deeds for cemetery purposes; presumption. Every deed of conveyance of real property to a religious corporation used for cemetery purposes, whether heretofore or hereafter recorded, shall be presumptive evidence that the conveyance vested in the grantee and its successors a fee simple absolute in the premises therein described, subject to the limitations and conditions therein prescribed, and that all proceedings prior thereto, including the consent of the court, if required, were regular and in accordance with all the provisions of law relating thereto. At the expiration of twenty years from the date of record of any such conveyance, heretofore or hereafter recorded, such presumption shall be conclusive.