remove failed streams.

[susnick]

https://github.com/susnick/iptv-checker/tree/wait

I was using this to check for offline streams. Its annoying when you want to watch a channel only to find out its not working. Unfortunately my provider is behind cloudflare and rate limits this, so larger playlists never complete. But something like this is an idea. I dont php in like 15 + years, so would need someone else to contribute.