Amir Khan Super Lightweight World ChampionshipAmir Khan now has an enviable dilemma.Fresh off disposing Zab Judah with a fifth-round knockout in their junior-welterweight world title unification fight Saturday in Las Vegas, Khan is at a best-of-both-worlds scenario.Khan, 24, can continue his dominance in the 140-pound class, amassing belts as he did after wresting Judah’s IBF title. For Kahn, who