The repo contains the CityBuild and associated objects that deal with building items in Citys.
Note: this should be set up using yarn as npm can't figure out a usable set of modules.
Add a generic RushProduction mechanism that could, for some type of Yield, complete production of the currently in-
progress item. It would need to return the cost for completion of the current item and there could be multiple available
(e.g. sacrifice population, spend Gold, spend Faith) and it should be selectable by the Player.