fix instruction comment

Author: tienbku

app/routes/turorial.routes.js

@@ -21,7 +21,7 @@ module.exports = app => {
   // Delete a Tutorial with id
   router.delete("/:id", tutorials.delete);
 
-  // Create a new Tutorial
+  // Delete all Tutorials
   router.delete("/", tutorials.deleteAll);
 
   app.use('/api/tutorials', router);