ATLANTA (AP) — Just like that, the Atlanta Hawks transformed themselves into a playoff contender. A team that averaged less than 25 wins the last three seasons added to its impressive young core with a whirlwind of free-agent signings. The latest came when Sacramento decided not match Atlanta’s four-year, $72 million offer sheet to Bogdan Bogdanovic. Flush with cash heading into free agency, the Hawks quickly signed forward Danilo Gallinari and guards Rajon Rondo and Kris Dunn. The signing of Bogdanovic was the icing on the cake of a six-day transformation that began with the drafting of USC center Onyeka Okongwu.