No municipality or county shall have power to license the sale of, or impose an excise tax upon, liquor as defined in this title, or to license the sale or distribution thereof in any manner; and any power now conferred by law on any municipality or county to license premises which may be licensed under this section, or to impose an excise tax upon liquor, or to license the sale and distribution thereof, as defined in this title, shall be suspended and shall be of no further effect: PROVIDED, That municipalities and counties shall have power to adopt police ordinances and regulations not in conflict with this title or with the regulations made by the board.