The state does hereby pledge to and agree with the holders of bonds issued N.H. Rev. Stat. § 12-G:17-28 that the state shall not limit or alter the rights hereby vested in the authority to fulfill the terms of any agreements made with the said holders of such bonds or in any way impair the rights and remedies of such holders until such bonds, together with the interest on them, with the interest on any unpaid installments of interest, and all costs and expenses in connection with any action or proceeding by or on behalf of such holders, are fully met and discharged. The authority is authorized to include this pledge and agreement of the state in any agreement with the holders of such bonds.