It’s now become an annual tradition. The Avett Brothers’ New Year’s Eve gig at the Neighborhood Theatre always sells out and is consistently one of the top shows of the year in Charlotte. Well, last year it was the best live show. The Avetts, Seth and Scott, along with Bob Crawford, weave a seamless version of bluegrass, replete with punk ethos, old-time country, folk and rock. Their newest recording, Emotionalism, was released this past May.