315.13 Action by resolution.—All action required or authorized to be taken under the provisions of this law by the governing body may be by resolution, which resolution may be adopted at the meeting of the governing body at which such resolution is introduced and shall take effect immediately upon such adoption. Except as otherwise provided in this law, no resolution under this law need be published or posted, nor shall any such resolution require for its passage more than a majority of all the members of the governing body then in office.