Writer Elizabeth Strout celebrated the release of her new book, “My Name Is Lucy Barton,’’ with Harvard Book Store at the Brattle Theatre on Tuesday night. Strout (pictured, with moderator Brock Clarke) is best known for the Pulitzer-winning novel “Olive Kitteridge,’’ which became an HBO miniseries that won six Emmys last fall. Strout told us last year that she wrote much of “Kitteridge’’ in Provincetown, in a cottage behind the Burger Queen.