Add mining commodities

[cintaracorp]

The mining commodities (such as Hephaestanite) seem to be in the shop data, though it is hard to get a summary of them. Perhaps a new Mining tab would be useful?

[richardthombs]

I see Hephaestanite is missing from the commodities menu option too. I think this is because nobody is selling it. I only threw the commodities page together to help me find some profitable trade routes and I don't do mining, so I didn't notice these were missing. I'll try and call out commodities that have no sellers into a separate page. That will probably identify mining and other harvestables.

[cintaracorp]

Clever idea!