Zombie movies have had a fascinating path to the mainstream. For decades, the creatures didn't have much of a presence or definition outside Voodoo lore, radioactive humanoids, and the unforgettable art of E.C. comics. Zombies were scarcely used, and when they were, they were a pretty far cry from the cannibalistic flesh-hungry creatures of the undead we know and love today. Then a gentleman and pioneering filmmaker named George A. Romero came along and changed the game forever. Romero didn't invent the zombie as he's often credited, but he did redefine it into a universal …