The mayor is hereby authorized to employ such additional personnel who shall serve at the pleasure of the mayor, and for such purposes an additional $100,000.00 per annum shall be made available for the salaries of such personnel from the city treasury. Said personnel shall not be subject to the provisions of the merit system. This section shall not limit the authority of said mayor to appoint other employees of said city under the provisions of the merit system or otherwise where authorized by any other law.