The income arising from any personal property held in any employees’ trust as defined in § 28-17-1 may be permitted to accumulate in accordance with the terms of the trust and the plan to which the trust forms a part for any time that may be necessary to accomplish the purposes for which the trust has been created. An employees’ trust shall not be deemed to be invalid as violating the rule against perpetuities or any law or rule against perpetuities or the suspension of the power of alienation of title to property, but may continue for any time that may be necessary to accomplish the purposes for which it has been created.