By William Schomberg LONDON (Reuters) - Some of the world's most powerful finance chiefs will meet in an English stately home on Friday and Saturday to try to speed up banking and finance reforms, with Cyprus' near meltdown fresh in their minds. Finance ministers and central bank governors from the Group of Seven industrialized economies probably will not break new ground on how to fix the weak world economy as discussions at the International Monetary Fund took place just three weeks ago. ...