The Eagles coach is thrilling his fans and angering rivals, but he doesn’t care as long as he’s helping his team PHILADELPHIA – To his own fans Nick Sirianni is the epitome of swag, the leader of the best football team in the NFL, and the steward of everything good and just in the football world. To opposing fans, he’s the obnoxious cheerleader with a clock ticking toward comeuppance. As with most things in life, the truth lies somewhere in between. During a 38-7 beatdown of the New York Giants in the divisional round of the postseason, Sirianni caught a…