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/AbstractContainerMenu.h

@@ -35,7 +35,7 @@ public:
 	static const int CONTAINER_ID_INVENTORY = 0;
 	static const int CONTAINER_ID_CREATIVE = -2;
 
-	vector<shared_ptr<ItemInstance> > lastSlots;
+	vector<shared_ptr<ItemInstance>> lastSlots;
 	vector<Slot *> slots;
 	int containerId;
 
@@ -95,7 +95,7 @@ public:
 	virtual bool stillValid(shared_ptr<Player> player) = 0;
 
 	// 4J Stu Added for UI
-	unsigned int getSize() { return (unsigned int)slots.size(); }
+	unsigned int getSize() { return static_cast<unsigned int>(slots.size()); }
 
 
 protected: