quvi/zdf: Support hd formats

THis commits also cleans up the code a bit.
quvi/zdf: Support live streams
quvi/ulmentv: Advertise default only since there is only one format
quvi/zdf: Advertise all available formats

This is actually a rewrite from simple search-one-url-parsing to
iterating them all and decide which one to use on some heuristics.