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/TimeCommand.cpp

@@ -81,5 +81,5 @@ shared_ptr<GameCommandPacket> TimeCommand::preparePacket(bool night)
 
 	dos.writeBoolean(night);
 
-	return shared_ptr<GameCommandPacket>( new GameCommandPacket(eGameCommand_Time, baos.toByteArray() ));
+	return std::make_shared<GameCommandPacket>(eGameCommand_Time, baos.toByteArray());
 }