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/WaterDropParticle.cpp

@@ -8,7 +8,7 @@
 WaterDropParticle::WaterDropParticle(Level *level, double x, double y, double z) : Particle(level, x, y, z, 0, 0, 0)
 {
     xd *= 0.3f;
-    yd = (float) Math::random() * 0.2f + 0.1f;
+    yd = static_cast<float>(Math::random()) * 0.2f + 0.1f;
     zd *= 0.3f;
 
     rCol = 1.0f;
@@ -19,7 +19,7 @@ WaterDropParticle::WaterDropParticle(Level *level, double x, double y, double z)
     gravity = 0.06f;
 
 	noPhysics = true;	// 4J - optimisation - do we really need collision on these? its really slow...
-    lifetime = (int) (8 / (Math::random() * 0.8 + 0.2));
+    lifetime = static_cast<int>(8 / (Math::random() * 0.8 + 0.2));
 }
 
 void WaterDropParticle::tick()