Before incurring any indebtedness under the provisions of sections 95.115 to 95.130, every city, incorporated town or village, whether organized under the general laws of this state or by special charter or by constitutional charter, shall provide for the collection of an annual tax on all taxable tangible property therein sufficient to pay the interest and principal of the indebtedness as they fall due, and to retire the same within twenty years from the date contracted.