Folk legend and actor Loudon Wainwright finishes the Jazz for the Opera House on Hallowe’en night. Mike McGrath-Bryan speaks with him on family, acting, and getting bottled at Páirc Ui Chaoimh. A musician, an actor, the great-great-grandson of a politician, and both progeny & progenitor of an immensely musical family, Loudon Wainwright III has done…