Add standalone file to be included in mods

`#include "beatsaber-hook/shared/early-mod-checks.hpp"` at the bottom
will ensure that the functions you have in your mod match on compile

shared/utils/early-mod-checks.hpp

@@ -0,0 +1,9 @@
+#pragma once
+
+// Include this file to assert that you have defined the necessary functions with the correct signatures
+
+#include <type_traits>
+#include "scotland2/shared/loader.hpp"
+
+static_assert(std::is_same_v<modloader::SetupFunc, &setup>, "Must match the specified signature with setup!");
+static_assert(std::is_same_v<modloader::LoadFunc, &load>, "Must match the specified signature with load!");