By Arshad Mohammed and Natalie Huet LONDON (Reuters) - Foreign ministers from the G8 group of rich countries failed to patch up deep divisions over Syria or come up with a concrete plan on North Korea during a meeting in London on Thursday. British Foreign Secretary William Hague, speaking after talks with his counterparts, admitted the world had done too little to try to resolve Syria's two-year-old conflict, in which an estimated 70,000 people have been killed. "The United Nations Security Council has not fulfilled its responsibilities because it is divided. That division continues. ...