Pass-through of HLS Interstitial tags in VOD2Live

[birme]

Support pass-through of HLS Interstitials tags [1][2] in VOD2Live.

[1] https://developer.apple.com/streaming/GettingStartedWithHLSInterstitials.pdf
[2] https://dev.to/video/inserting-hls-interstitials-for-an-existing-vod-library-gbi

[birme]

Will provide some example VODs before we start working on this one.

[birme]

Here is an example VOD with HLS interstitial and server-side inserted ad segments that the Channel Engine should handle (by just passing through HLS interstitial tags). IDs and start-date needs to be recalculated for the VOD2Live stream.

https://lambda-ssl.eyevinn.technology/stitch/master.m3u8?payload=ewogICAgICAidXJpIjogImh0dHBzOi8vbWFpdHYtdm9kLmxhYi5leWV2aW5uLnRlY2hub2xvZ3kvVklOTi5tcDQvbWFzdGVyLm0zdTgiLAogICAgICAiYnJlYWtzIjogWwogICAgICAgIHsgInBvcyI6IDAsICJkdXJhdGlvbiI6IDE1MDAwLCAidXJsIjogImh0dHBzOi8vbWFpdHYtdm9kLmxhYi5leWV2aW5uLnRlY2hub2xvZ3kvYWRzL2Fwb3RlYS0xNXMubXA0L21hc3Rlci5tM3U4IiB9LAogICAgICAgIHsgInBvcyI6IDU1MDAwLCAiZHVyYXRpb24iOiAxNTAwMCwgInVybCI6ICJodHRwczovL21haXR2LXZvZC5sYWIuZXlldmlubi50ZWNobm9sb2d5L2Fkcy9hcG90ZWEtMTVzLm1wNC9tYXN0ZXIubTN1OCIgfQogICAgICBdCn0=&c=1