[UI/UX] Replace embedded YouTube videos with gameplay video from ScreenScraper

[milktoastrat]

I think it could look cleaner if we used the gameplay footage hosted by ScreenScraper instead of embedding from YouTube. It would prevent the youtube suggested videos after the video ends. AND it would standardize all of the videos to be the same thing- Gameplay capture. Right now, some youtube videos are gameplay, some are trailers, etc.

[gantoine]

This would require downloading all the video files locally, since SSFR doesn't allow playing videos from browser contexts where you're not logged in, which would take a toooon of space on disk.