Update README.md

Author: nandikajain

README.md

@@ -30,7 +30,7 @@ Development setup
 3. Run `npm install` to install the dependencies and build the project
 4. Edit the code
 5. Run `npm run-script release` to (re-)build all necessary files into the deploy directory
-6. Run `serve deploy` to run the server locally, by installing serve by using `npm install serve -g`.
+6. Run `serve deploy/` to run the server locally, by installing serve by using `npm install serve -g`.
 
 Visit [http://localhost:3000](http://localhost:3000) to use WebVOWL.