GLENDALE, Ariz. — ‘‘Super’’ Joe McEwing knows something about leadership, having been a leader himself even as a utility player for the New York Mets and St. Louis Cardinals. McEwing, the White Sox’ third-base coach, was the lead-by-example type who used every ounce of energy to squeeze out every bit of ability in his body. Tony La Russa loved the way he went about his business so much, he requested a pair of McEwing’s spikes when the Cardinals traded him. He is a manager in the making — perhaps as Robin Ventura’s replacement with the Sox — and so he …