Retainer UI update

[Elamys]

I'm pretty sure that something has sold if my retainer was selling 20 items when last we met, and they are currently selling 14 items. That information is always up-to-date on the retainer UI.

I have the maximum amount of retainers and usually they're all selling something, but I don't always max them out, so it's a lot of numbers to keep track of. I can't always remember how many items each of them had the last time I played, therefore I have to summon them to see if they sold anything.