"Henceforth, applicants for a variance may establish unnecessary hardship by proof that:

(1) a zoning restriction as applied to their property interferes with their reasonable use of the property, considering the unique setting of the property in its environment;

(2) no fair and substantial relationship exists between the general purposes of the zoning ordinance and the specific restriction on the property; and

(3) the variance would not injure the public or private rights of others."