Sections 3-501 to 3-514 shall be full authority for the creation of airport authorities by cities, and for the exercise of the powers therein granted to cities and to such authorities, and no action, proceeding or election shall be required prior to the creation of airport authorities hereunder or to authorize the exercise of any of the powers herein granted, any provision of law or of any city charter to the contrary notwithstanding, and the proceedings of the mayor and council of any city heretofore taken for the creation and establishment of an airport authority are hereby ratified, validated and confirmed.