message: Set YieldTable data type explicitly to MineVein
  This matched with the MineVein type definition, and was required to be
  the same, based on usage, but the link wasn't explicit before.
diff: * [2] Rare Metals
  * [3] Rare Minerals
  */
  -static const std::map<MineProductionRate, std::array<int, 4>> YieldTable =
  +static const std::map<MineProductionRate, Mine::MineVein> YieldTable =
  {
  {MineProductionRate::Low, {600, 500, 600, 500}},
  {MineProductionRate::Medium, {700, 550, 700, 550}},
  