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/StructureStart.cpp

@@ -9,14 +9,14 @@
 StructureStart::StructureStart()
 {
 	chunkX = chunkZ = 0;
-	boundingBox = NULL;		// 4J added initialiser
+	boundingBox = nullptr;		// 4J added initialiser
 }
 
 StructureStart::StructureStart(int x, int z)
 {
 	this->chunkX = x;
 	this->chunkZ = z;
-	boundingBox = NULL;
+	boundingBox = nullptr;
 }
 
 StructureStart::~StructureStart()