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/Common/UI/UIControl_CheckBox.cpp

@@ -60,7 +60,7 @@ void UIControl_CheckBox::init(UIString label, int id, bool checked)
 bool UIControl_CheckBox::IsChecked()
 {
 	rrbool checked = false;
-	IggyResult result = IggyValueGetBooleanRS ( &m_iggyPath , m_checkedProp, NULL, &checked );
+	IggyResult result = IggyValueGetBooleanRS ( &m_iggyPath , m_checkedProp, nullptr, &checked );
 	m_bChecked = checked;
 	return checked;
 }