CNN is planning a substantial investment in new programming, with a heavy emphasis on acquiring unscripted shows by outside producers in the vein of “Anthony Bourdain’s Parts Unknown” and films like “Blackfish.” The strategy, which is now being touted to analysts and investors, will hamper CNN's revenue but is meant to shore up its viewership in key demographics and reduce its dependence on coverage of big breaking news stories to attract viewers and advertisers. As a start, Bourdain may be getting a CNN talk show on top of his Sunday evening "Parts Unknown" program. A live special to be hosted...