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/WitherBossRenderer.cpp

@@ -48,7 +48,7 @@ void WitherBossRenderer::scale(shared_ptr<LivingEntity> _mob, float a)
 	int inTicks = mob->getInvulnerableTicks();
 	if (inTicks > 0)
 	{
-		float scale = 2.0f - (((float) inTicks - a) / (SharedConstants::TICKS_PER_SECOND * 11)) * .5f;
+		float scale = 2.0f - ((static_cast<float>(inTicks) - a) / (SharedConstants::TICKS_PER_SECOND * 11)) * .5f;
 		glScalef(scale, scale, scale);
 	}
 	else