No building or structure hereafter erected or altered and no building in which the occupancy or nature of use shall have been changed, shall be occupied or used in whole or in part for any purpose whatsoever unless and until a Certificate of Occupancy shall have been issued therefor by the Building Inspector. The issuance of a Certificate of Occupancy shall negate the necessity of securing a Zoning Permit for the same premises. The issuance of a Certificate of Occupancy shall supersede and revoke any Zoning Permit already granted for the same premises.