The certificate of incorporation or the by-laws of any corporation may provide that in all elections of directors of such corporation each member shall be entitled to as many votes as shall equal the number of votes which, except for such provisions as to cumulative voting, he would be entitled to cast for the election of directors multiplied by the number of directors to be elected, and that he may cast all of such votes for a single director or may distribute them among the number to be voted for, or for any two or more of them, as he may see fit, which right, when exercised, shall be termed cumulative voting.