Removed use of GM_addStyle. YouTube Center can now add/remove style elements dynamically. This means that YouTube Center don't have to reload the page a second time when another YouTube experimental layout is detected. Removed function $AddStyle, because it's not needed anymore and it was outdated. The settings button have now been moved down to the appbar when using the experimental layout and is logged out, because the settings menu button added by YouTube isn't visible when logged out.