Switching your Vaadin application between Tomcat and Google App Engine

While development, it's often required one to switch between the localhost (let's say tomcat) and GAE. How does one do it?

If you want to deploy your application to GAE, follow this link.
If you want to  deploy to tomcat, follow these steps:

Step 1. Change your web.xml to  have the servlet-class as VaadinServlet (instead of GAEVaadinServlet)      
         <servlet-name>myservlet</servlet-name>
         <servlet-class>com.vaadin.server.VaadinServlet</servlet-class>

Step 2. Deploy to your localhost. Right click -> Run As -> Run on Server