Reuters: The United Nations took a step toward a new climate treaty on Friday by publishing the first draft negotiating texts outlining widely varying options for rich nations to cut greenhouse gas emissions. Two documents totaling 68 pages also laid out choices on controversial issues such as nuclear power, emissions trading, forests, shipping or aviation in a new U.N. global warming pact due to be agreed in Copenhagen in December. “Key U.N. negotiating texts, which will form the basis …