Fetches FLV URL from "sdURL" in addVariable("sequence") JSON,
instead of addVariable("video") which doesnot exist today.
Supports new title, uploader nickname format.
This, in particular, lets me grab the videos from the beginners channel with
URLs like:
http://vimeo.com/groups/fivebyfive/videos/22648611
Note that the regexp *will* break for other URLs that we don't know about
and that's on purpose: we don't want to accidentally grab videos that would
be passed on to other information extractors.