Add API to control shadow intensity from the game/mod (#11944)

* Also Disable shadows when sun/moon is hidden. Fixes #11972.

src/script/lua_api/l_object.h

@@ -376,4 +376,10 @@ class ObjectRef : public ModApiBase {
 
 	// set_minimap_modes(self, modes, wanted_mode)
 	static int l_set_minimap_modes(lua_State *L);
+
+	// set_lighting(self, lighting)
+	static int l_set_lighting(lua_State *L);
+	
+	// get_lighting(self)
+	static int l_get_lighting(lua_State *L);
 };