(a) The powers conferred by this act shall be in addition and supplemental to the powers conferred by any other law.
(b) Nothing contained in this act shall affect the term of office of any commissioner of a housing authority heretofore appointed.
(c) The enactment of this act shall not be construed to render invalid any action or proceeding had or taken for the creation or establishment of a housing authority pursuant to laws in existence prior to the enactment of this act.