(Reuters) - Snap Inc lost more users than Wall Street expected in the third quarter as it continued to grapple with an unpopular redesign of its Snapchat photo-messaging app and fierce competition from Facebook Inc's Instagram.Daily active users are expected to fall again next quarter, Snap Chief Financial Officer Tim Stone told analysts on a conference call, which would mark the third sequential quarter of user declines. Snap shares, which have lost more than 52 percent since the beginning of..