In this age of teenage monsters, you wouldn’t think another dip into that pool would be that compelling. Especially when it’s based on a jokey, low budget eighties flick. But MTV’s “Teen Wolf” bucked the trends. Providing compelling entertainment that didn’t feel like a rip-off of any other property. This Sunday, the series returns for second season. Will it maintain the momentum of season one? Or will it fail to recapture that magic?