Ernest Hemingway was a maker of lists and a collector of his life’s ephemera. For the first time, some of the objects that this American writer gathered during his long career — bullfighting stubs from Pamplona in Spain, boastful fishing logs from expeditions off the Cuban coast, coy letters to a mistress, penciled drafts of stories — will be on display in an exhibition at the Morgan Library & Museum from Sept. 25 through Jan. 31.