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/EnderCrystalRenderer.cpp

@@ -25,7 +25,7 @@ void EnderCrystalRenderer::render(shared_ptr<Entity> _crystal, double x, double
 
 	float tt = crystal->time + a;
 	glPushMatrix();
-	glTranslatef((float) x, (float) y, (float) z);
+	glTranslatef(static_cast<float>(x), static_cast<float>(y), static_cast<float>(z));
 	bindTexture(&ENDER_CRYSTAL_LOCATION);
 	float hh = sin(tt * 0.2f) / 2 + 0.5f;
 	hh = hh * hh + hh;