SCTE 35 at the edge

Deal with SCTE-35 ad markers at the edge.

TODOs

• As requests come in for an m3u8
  • request the m3u8 from the origin
  • extract SCTE markers from the meu8
  • store in list if not already there
  • process marker
    • retrieve ad
    • transcoding??
    • replace in manifest with new ad segment
  • remove marker once processed
• ts requests?
• fmp4 requests?
• cmaf?