Add ability to bind typed arrays to script API

Note: Only replaced 2 instances to test, Node.get_children and TileMap.get_used_cells
Note: Will do a mass replace on later PRs of whathever I can find, but probably need
a tool to grep through doc.
Warning: Mono will break, needs to be fixed (and so do TypeScript and NativeScript, need to ask respective maintainers)

modules/gdnative/nativescript/nativescript.h

@@ -133,6 +133,8 @@ protected:
 public:
 	inline NativeScriptDesc *get_script_desc() const;
 
+	bool inherits_script(const Ref<Script> &p_script) const;
+
 	void set_class_name(String p_class_name);
 	String get_class_name() const;