2.9 2021-02-07

svtplay: fix issue finding videos on the new site
svt: add support for downloading videos from the recpie site
urplay: fix issue finding some videos
discoveryplus: add support for it
discoveryplus: show a better error message when people need the right cookie
changed behavior when using –merge-subtitle, it will force –subtitle
add support for –only-audio and –only-video, it will only work when audio and video is separate