Cannes, France, home to the famous international film festival, is also the host city for the first major boat show of the European season. At this year’s Festival de la Plaisance de Cannes (www.salonnautiquecannes.com), 580 yachts, tenders, and sailboats of all types and sizes were on display. Some 150 of these vessels made their Mediterranean debuts at the show. And as usual, the yachts looked as elegant, dramatic, and classy on the water as actors do on the red carpet. Here are some of the new vessels that …