message: Remove Planet x/y read methods
  Use `position()` instead.
diff: @@ -39,9 +39,6 @@ public:
  void position(const NAS2D::Point<int>& point) { mPosition = point; }
  void position(int x, int y) { mPosition = {x, y}; }
  - int x() const { return mPosition.x(); }
  - int y() const { return mPosition.y(); }
  -
  int digDepth() const { return mMaxDigDepth; }
  int maxMines() const { return mMaxMines; }
  