Youtube Livestreams Theater Mode

Adds an enhanced theater mode to youtube livestreams with the following features:
– displaying chat next to video
– move chat to the left side
– show chat on top of the video
– display livestream information on hover over the video

Available settings:
– force dark theme in theater mode
– chat width (next to video)
– chat width (over video)

Permissions:
– storage permission is needed to save settings

Other browsers:
– available as a Firefox add-on: https://addons.mozilla.org/en/firefox/addon/youtubelivestreamstheatermode/