292.15 Taxation and appropriation.—The boards of county commissioners of the several counties of the state be and the same are hereby expressly authorized and empowered to levy a tax not to exceed one-half mill, or use available funds on hand and unappropriated, whether derived from taxation or otherwise, for the purpose of aiding and assisting the veterans described in s. 292.10, by providing a veteran service officer and maintaining a veteran service office in said county, and to disburse said moneys at such times and in such manner and under such terms and conditions as may be provided by resolution of said boards of county commissioners from time to time.