The distinction between an accessory before the fact and a principal, and between principals in the first and second degree, in cases of felony, is abrogated, and all persons concerned in the commission of a felony, whether they directly commit the act constituting the offense, or aid and abet in its commission, though not present, must be prosecuted, tried and punished as principals, and no additional facts need be alleged in any indictment or information against such an accessory than are required in an indictment or information against his principal.