A settlement deal between Chicago and three online travel companies in April secured the city $18 million just hours before a state appeals court ruled to vacate a $29.1 million tax award in the underlying case, according to documents the city released Tuesday.The deal was struck before the 1st District Appellate Court issued an opinion reversing a 2013 summary judgment in Cook County Circuit Court against Expedia for underpaying city hotel taxes by $29.1 million.Just before the 1st District ruling was released to the …