Puts 7tv stream latency in player controls
To use this script you must enable the 7tv "Video Stats" setting :)
Based on https://greasyfork.org/en/scripts/465533-twitch-latency-on-player-controls-ffz-version
which I based on https://greasyfork.org/en/scripts/391680-twitch-latency-on-player-controls/
