(Reuters) - CBS has dropped its lawsuit accusing rival ABC of copying its long-running reality TV series "Big Brother" when it created "The Glass House," which has drawn low ratings. The lawsuit had claimed that "The Glass House," which began airing in June, mimicked several elements of "Big Brother," which began airing in 2000, and even employed 19 former producers and staff from that show. Both shows involve contestants who are filmed continuously as they live in a large house, and who are evicted over time. ...