Except as provided in Sections 7.11 and 7.12, no obligations shall be issued to pay current expenses, but the Council may issue and sell obligations for any other municipal purpose in accordance with law and within the limitations prescribed by law. No such obligations shall be issued and sold without the approval of the majority of the voters voting on the question at a general or special election, except in the case of obligations for which an election is not required by this Charter or by law.