Jon Langford is responsible for way too much great art for you not to know who he is. To begin at the beginning, he’s one of two remaining original members of the Mekons, singing and playing guitar in the increasingly difficult-to-categorize onetime punk band he founded while studying art at the University of Leeds, England, in 1977. Their albums Fear and Whiskey and Edge of the World, from 1985 and 1986, respectively, were among…