Change gold bar loot items to stamped gold bars.

[Joefesok]

Currently Gold Bars are a very confusing concept for new players since some gold bars are worth a shitload of money, and the bars manufactured stationside are almost completely worthless. I think the easiest change is to just change all of the "loot" gold bars- the ones actually worth something- into stamped gold bars. Suggestions I've heard so far are stamped spanish gold bullion from the 1700s, or stamped space spanish gold bullion from the 2010s.