Tweak frustum.
Fix castle flags, pikeman and archer tabards.
Split population info out of Farmland, created new Village class.
Added EconActor class, reading from save, ownership in Farmland, multiple goods.
Labour-needed calculation in farms.
Create Market class.
Read prices from save.
Price finding in Market class.
Trading code.
Deliver labour to farms.
Reorganise order of end-of-turn operations.
Fix off-by-one bug in labour delivery.
Add castles to holdMarket method.
Fix iteration error in getBids.
Separate production phase; reimplement contracts.
Fix order-of-construction issue with contracts.
Maslow hierarchy utilities.
Add Industry class.
Read farm capital from file.
Move goods field to popInfo - doesn't belong in the save.