ISTANBUL (Reuters) - U.S. Vice President Joe Biden said on Saturday that the United States and Turkey were prepared for a military solution against Islamic State in Syria should the Syrian government and rebels fail to reach a political settlement. The latest round of Syria peace talks are planned to begin on Monday in Geneva but were at risk of being delayed partly because of a dispute over who will comprise the opposition delegation. Syrian armed rebel groups said on Saturday they held the Syrian government and Russia responsible for any failure of peace talks to end the country's civil...