“employer” means any person (excluding any person not acting as a principal, but including any person acting in a fiduciary capacity or in his capacity as a trustee in an insolvent estate, an executor or an administrator of a benefit fund, pension fund, pension preservation fund, provident fund, provident preservation fund, retirement annuity fund or any other fund) who pays or is liable to pay to any person any amount by way of remuneration, and any person responsible for the payment of any amount by way of remuneration to any person under the provisions of any law or out of public funds (including the funds of any provincial council or any administration or undertaking of the State) or out of funds voted by Parliament or a provincial council;