Some South End arrivistes may criminally overlook Vejigantes, a lively, colorful outpost of Puerto Rican cuisine. What’s your excuse? Have something against tropical cocktails? Turnovers and fritters not paleo enough? Allergies prevent you from enjoying a gumbo of lobsters, shrimp, squid, octopus and clams? Ethically opposed to steaks and chops? Mystified as to what a mofongo is? No? So you don’t have an excuse. What are you waiting for?