I'm fairly certain some component of the Auctioneer package adds something like that to your tooltips.
Also, unrelated to your question, I see you have an "Interface" folder inside your AddOns folder. This probably means you installed an addon, but it never showed up in-game. Inside that extra folder I bet you'll see another "AddOns" folder, and inside that an addon that needs to be moved up in your actual AddOns folder. :P