Modernize project codebase (#906)

* 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

* Add safety checks and fix a issue with vector going OOR

Minecraft.World/FollowParentGoal.cpp

@@ -33,7 +33,7 @@ bool FollowParentGoal::canUse()
 	}
 	delete parents;
 
-	if (closest == NULL) return false;
+	if (closest == nullptr) return false;
 	if (closestDistSqr < 3 * 3) return false;
 	parent = weak_ptr<Animal>(closest);
 	return true;
@@ -41,7 +41,7 @@ bool FollowParentGoal::canUse()
 
 bool FollowParentGoal::canContinueToUse()
 {
-	if (parent.lock() == NULL || !parent.lock()->isAlive()) return false;
+	if (parent.lock() == nullptr || !parent.lock()->isAlive()) return false;
 	double distSqr = animal->distanceToSqr(parent.lock());
 	if (distSqr < 3 * 3 || distSqr > 16 * 16) return false;
 	return true;