Project modernization (#630)

* Fixed boats falling and a TP glitch #266

* Replaced every C-style cast with C++ ones

* Replaced every C-style cast with C++ ones

* Fixed boats falling and a TP glitch #266

* Updated NULL to nullptr and fixing some type issues

* Modernized and fixed a few bugs

- Replaced most instances of `NULL` with `nullptr`.
- Replaced most `shared_ptr(new ...)` with `make_shared`.
- Removed the `nullptr` macro as it was interfering with the actual nullptr keyword in some instances.

* Fixing more conflicts

* Replace int loops with size_t and start work on overrides

Minecraft.World/RotatedPillarTile.cpp

@@ -73,5 +73,5 @@ int RotatedPillarTile::getType(int data)
 
 shared_ptr<ItemInstance> RotatedPillarTile::getSilkTouchItemInstance(int data)
 {
-	return shared_ptr<ItemInstance>( new ItemInstance(id, 1, getType(data)) );
+	return std::make_shared<ItemInstance>(id, 1, getType(data));
 }