Bookies see Europe stocks extending sell-off

PARIS, June 16 (Reuters) - Financial bookmakers expect the leading European benchmark indexes to fall on Thursday, adding to the previous session's sell-off on mounting worries over Greece's debt crisis. Financial spreadbetters expect Britain's FTSE 100 to open 18 to 30 points lower, or as much as 0.5 percent, Germany's DAX to open 14 to 28 points lower, or as much as 0.4 percent, and France's CAC-40 to open 24 to 33 points lower, or as much as 0.9 per