Any other law to the contrary notwithstanding, any municipality may authorize, sell, issue and deliver its bonds without regard to whether or not notice and hearing on the plans, specifications and form of contract for the public improvement to be paid for in whole or in part from the proceeds of said bonds has theretofore been given, and without regard to whether or not any contract has theretofore been awarded for the construction of said improvement. The foregoing provision shall not apply to bonds which are payable solely from special assessment levied against benefited property.