For snowbirds heading south soon, an overnight (or longer) stay in Hampton, Virginia, offers one of the better treats on the entire trip. As the real estate people say, it’s all about location, location, location. And here, Hampton is pretty much at the top of the list. It’s almost next to Norfolk and Mile Zero of the ICW (the Julia Tuttle Causeway in Miami is at Mile 1,087), and it also offers a rich variety of marinas, history, museums, parks, restaurants, and things to see and do. By boat, Hampton is easy to get to. It’s a natural harbor at…