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/TntRenderer.cpp

@@ -17,7 +17,7 @@ void TntRenderer::render(shared_ptr<Entity> _tnt, double x, double y, double z,
 	shared_ptr<PrimedTnt> tnt = dynamic_pointer_cast<PrimedTnt>(_tnt);
 
 	glPushMatrix();
-    glTranslatef((float) x, (float) y, (float) z);
+    glTranslatef(static_cast<float>(x), static_cast<float>(y), static_cast<float>(z));
     if (tnt->life - a + 1 < 10)
 	{
         float g = 1 - ((tnt->life - a + 1) / 10.0f);