StreamBuffer: don't check fragment overlapping in case of live playlists or VoD playlist that slided in the past
StreamBuffer: don't check fragment overlapping in case of live playlists or VoD playlist that slided in the past

fix macroblocks and freeze on live

clappr/flashls,mangui/flashls,clappr/flashls,jlacivita/flashls,fixedmachine/flashls,neilrackett/flashls,codex-corp/flashls,tedconf/flashls,mangui/flashls,hola/flashls,hola/flashls,jlacivita/flashls,codex-corp/flashls,vidible/vdb-flashls,tedconf/flashls,vidible/vdb-flashls,fixedmachine/flashls,NicolasSiver/flashls,NicolasSiver/flashls,neilrackett/flashls