Update to let customers know when stock is getting low

One of the features I like about www.sparkfun.com is that they let the user know when the stock on items are getting low. through the use of a traffic light format: green = ok, yellow = running low, red = out of stock.

I managed to tweak the code to consider not just stock levels but threshold levels as well and display the same colored icons. (Updated throbber2.gif)

Works pretty nice.