stream.hds: Major refactoring.
stream.hds: Major refactoring.

Use the segmented stream and flv concat interfaces
to simplify code.

Dobatymo/livestreamer,Dobatymo/livestreamer,wolftankk/livestreamer,fishscene/streamlink,caorong/livestreamer,Feverqwe/livestreamer,bastimeyer/streamlink,wlerin/streamlink,ethanhlc/streamlink,Masaz-/livestreamer,chhe/livestreamer,charmander/livestreamer,Feverqwe/livestreamer,okaywit/livestreamer,ethanhlc/streamlink,gravyboat/streamlink,back-to/streamlink,charmander/livestreamer,fishscene/streamlink,flijloku/livestreamer,chhe/livestreamer,javiercantero/streamlink,flijloku/livestreamer,streamlink/streamlink,melmorabity/streamlink,beardypig/streamlink,bastimeyer/streamlink,chhe/streamlink,Saturn/livestreamer,derrod/livestreamer,gravyboat/streamlink,chrippa/livestreamer,programming086/livestreamer,javiercantero/streamlink,jtsymon/livestreamer,Masaz-/livestreamer,sbstp/streamlink,back-to/streamlink,lyhiving/livestreamer,chrippa/livestreamer,beardypig/streamlink,mmetak/streamlink,chhe/streamlink,Saturn/livestreamer,melmorabity/streamlink,gtmanfred/livestreamer,hmit/livestreamer,wlerin/streamlink,sbstp/streamlink,intact/livestreamer,streamlink/streamlink,jtsymon/livestreamer,blxd/livestreamer,intact/livestreamer,Klaudit/livestreamer,Klaudit/livestreamer,caorong/livestreamer,mmetak/streamlink,programming086/livestreamer,wolftankk/livestreamer,gtmanfred/livestreamer,okaywit/livestreamer,lyhiving/livestreamer,derrod/livestreamer,blxd/livestreamer,hmit/livestreamer