Add rare goods avaliability to stations

[Forecaster]

"Did you plan to make it possible to put rare goods in the station- info in any way? For example: Choice 'Rare Goods' It could open a small field in which you can type in the 'rare goods' and estimated tons/price - a small symbol in Stations/System field could show you there is some rare goods available in the system."

• CMDR Decus Crux