Add default copy constructors to Color and Position classes

src/client/position.h

@@ -36,6 +36,8 @@ public:
     Position() : x(65535), y(65535), z(255) { }
     Position(uint16 x, uint16 y, uint8 z) : x(x), y(y), z(z) { }
 
+    Position(const Position &position) = default;
+
     Position translatedToDirection(Otc::Direction direction) {
         Position pos = *this;
         switch(direction) {