LONDON (Reuters) - The risks to Britain from a disorderly collapse of the euro zone are huge and Greece has to make up its mind over its membership of the zone, finance minister George Osborne said on Thursday. In comments likely to stir up resentment on the continent, where euro zone leaders are fed up with what they see as an obstructive Britain lecturing from the sidelines, Osborne told the bloc to form a banking union and underwrite its banks. ...