Groton — An art teacher wanted to create a “sub trail” as part of the celebration of the 100th anniversary of the arrival of the first submarine to the U.S. Naval Submarine Base, and her idea has taken hold. Teacher Joy Supples’ plan was to have local artists create a “fleet” of submarine sculptures, similar to the “Whale Tail” art project in New London a few years ago. About a dozen sponsors have come forward …