AMHERST, Mass. - On the twentieth anniversary of the publication of Will Eisner’s "A Contract with God," the first work to be published as a serious comic book, or "graphic novel," the University of Massachusetts will host a conference on the history, aesthetics, and future of the rapidly growing genre. The conference is co-sponsored by the UMass departments of comparative literature, English, art history, and Judaic and Near Eastern studies, in conjunction with the Words & Pictures Museum in Northampton, Mass., and Kitchen Sink Press. The Words & Pictures Museum will also present an exhibition on the graphic novel the same weekend.