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/BatRenderer.cpp

@@ -7,7 +7,7 @@ ResourceLocation BatRenderer::BAT_LOCATION = ResourceLocation(TN_MOB_BAT);
 
 BatRenderer::BatRenderer() : MobRenderer(new BatModel(), 0.25f)
 {
-	modelVersion = ((BatModel *)model)->modelVersion();
+	modelVersion = static_cast<BatModel *>(model)->modelVersion();
 }
 
 void BatRenderer::render(shared_ptr<Entity> _mob, double x, double y, double z, float rot, float a)