Add tracking for YouTube videos #2156

This is a WIP. I'm tracking the following events right now

1. Load event for YouTube videos
2. Play/Paused/Buffering/Finished status of the video
3. Video Quality
4. Errors, reported by YouTube API
5. 10% increments of video played.
Yes, you can use advanced search: https://developer.mozilla.org/en-US/search?locale=*&page=1&html_attributes=src%3D%22https%3A%2F%2Fwww.youtube.com