One day, we’ll hopefully live in a world where major games make their Mac debuts alongside their PC and console counterparts. Until then, we can be thankful that big titles do pop up in the Mac App Store only a few months later. The most recent such release is Feral Interactive’s port of XCOM: Enemy Unknown - Elite Edition ($50). Winner of multiple game of the year awards from 2012, the turn-based tactical role-playing strategy game will…