Remove all MSVC __int64 (#742)

Minecraft.World/SwampRiversLayer.h

@@ -5,7 +5,7 @@
 class SwampRiversLayer : public Layer
 {
 public:
-	SwampRiversLayer(__int64 seed, shared_ptr<Layer> parent);
+	SwampRiversLayer(int64_t seed, shared_ptr<Layer> parent);
 
 	intArray getArea(int xo, int yo, int w, int h);
 };