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.World/SimplexNoise.cpp

@@ -49,7 +49,7 @@ SimplexNoise::~SimplexNoise()
 
 int SimplexNoise::fastfloor(double x)
 {
-	return x > 0 ? (int) x : (int) x - 1;
+	return x > 0 ? static_cast<int>(x) : static_cast<int>(x) - 1;
 }
 
 double SimplexNoise::dot(int *g, double x, double y)