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/ScreenSizeCalculator.cpp

@@ -21,10 +21,10 @@ ScreenSizeCalculator::ScreenSizeCalculator(Options *options, int width, int heig
 	{
 		scale = forceScale;
 	}
-    rawWidth = w / (double) scale;
-    rawHeight = h / (double) scale;
-    w = (int) ceil(rawWidth);
-    h = (int) ceil(rawHeight);
+    rawWidth = w / static_cast<double>(scale);
+    rawHeight = h / static_cast<double>(scale);
+    w = static_cast<int>(ceil(rawWidth));
+    h = static_cast<int>(ceil(rawHeight));
 }
 
 int ScreenSizeCalculator::getWidth()