[TIMOB-18879] Windows: Allow casting to a different native type

We should allow the ability to "upcast". We could simply hang a "JSObject Platform::Object::cast(std::string& type)" method that is on all native wrapped objects and would take the new type name. Then we'd have a giant generated if/else block where we test against the known set of type names and do the unwrapping/wrapping to "cast" it:

auto wrapped_object = unwrap();
auto new_type = js_context.CreateObject(JSExport<Titanium::Windows::UI::Xaml::Controls::Page>::Class());
auto new_wrapper = new_type.GetPrivate<Titanium::Windows::UI::Xaml::Controls::Page>();
new_wrapper->wrap(dynamic_cast<Windows::UI::Xaml::Controls::Page>(wrapped_object));
return new_type;