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/DripParticle.cpp

@@ -30,7 +30,7 @@ DripParticle::DripParticle(Level *level, double x, double y, double z, Material
 	this->material = material;
 	stuckTime = 40;
 
-	lifetime = (int) (64 / (Math::random() * 0.8 + 0.2));
+	lifetime = static_cast<int>(64 / (Math::random() * 0.8 + 0.2));
 	xd = yd = zd = 0;
 }