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/GameModeCommand.cpp

@@ -37,7 +37,7 @@ void GameModeCommand::execute(shared_ptr<CommandSender> source, byteArray comman
 
 GameType *GameModeCommand::getModeForString(shared_ptr<CommandSender> source, const wstring &name)
 {
-	return NULL;
+	return nullptr;
 	//if (name.equalsIgnoreCase(GameType.SURVIVAL.getName()) || name.equalsIgnoreCase("s")) {
 	//	return GameType.SURVIVAL;
 	//} else if (name.equalsIgnoreCase(GameType.CREATIVE.getName()) || name.equalsIgnoreCase("c")) {