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/EmptyMapItem.cpp

@@ -23,7 +23,7 @@ shared_ptr<ItemInstance> EmptyMapItem::use(shared_ptr<ItemInstance> itemInstance
 
 	//data.setDirty();
 
-	shared_ptr<ItemInstance> map = shared_ptr<ItemInstance>( new ItemInstance(Item::map, 1, -1) );
+	shared_ptr<ItemInstance> map = std::make_shared<ItemInstance>(Item::map, 1, -1);
 	Item::map->onCraftedBy(map, level, player);
 
 	itemInstance->count--;