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.Client/MinecraftServer.h

@@ -52,9 +52,9 @@ typedef struct _NetworkGameInitData
 	_NetworkGameInitData()
 	{
 		seed = 0;
-		saveData = NULL;
+		saveData = nullptr;
 		settings = 0;
-		levelGen = NULL;
+		levelGen = nullptr;
 		texturePackId = 0;
 		findSeed = false;
 		xzSize = LEVEL_LEGACY_WIDTH;
@@ -236,8 +236,7 @@ private:
 public:
 	void					addPostProcessRequest(ChunkSource *chunkSource, int x, int z);
 
-public:
-	static PlayerList *getPlayerList() { if( server != NULL ) return server->players; else return NULL; }
+    static PlayerList *getPlayerList() { if( server != nullptr) return server->players; else return nullptr; }
 	static void SetTimeOfDay(int64_t time) { setTimeOfDayAtEndOfTick = true; setTimeOfDay = time; }
 	static void SetTime(int64_t time) { setTimeAtEndOfTick = true; setTime = time; }