Corporate mergers and buyouts seem to be changing the names of D.C.’s familiars in recent months. First Verizon (now Qwest?) moves to grab MCI, throwing the name of the MCI Center into flux, and now May Department Stores Co., owner of area stores Hecht’s and Filene’s, announces a merger with Federated Department Stores Inc. (Macy’s and Bloomingdale’s). Once consummated, Federated will operate more than 950 department stores, along with approximately 700 bridal and formalwear stores….