When Ray Dalio was growing up on Long Island, he used to love watching TV documentaries by Jacques Cousteau, the French oceanographer. Now Dalio, 71, and the founder of one of the largest hedge funds in the U.S., is launching OceanXplorer, his own 286-foot research vessel, with three miniature submarines and two underwater robots, to explore the oceans of the world himself. He also will make some documentaries of his own, starting with a six-part series for National Geographic, produced by the BBC with James Cameron, the director of The Titanic, as executive producer. Dalio is best known as the…