Large quality of life update to Lumina:
1) Fix up the applauncher desktop plugins so that the initial sizing is sane.
2) Completely remove all global static variables from the session.
3) Re-enable the login/logout chimes (works properly without static variables)
4) Streamline the desktop background rotation algorithms a bit.
5) Greatly streamline the Session start procedure (50% to 75% faster on my computer here)
6) Make sure the background wallpaper does not rotate every time the desktop settings file changes (only when the backgrounds for that desktop are changed, or the rotation timer goes off)