CSE321 Tomcat Docker setup

This is the configuration I'm using for running Apache Tomcat in CSE321. To set it up, type ./run.sh in the root directory; press C-c to kill the server. By default, the server listens on port 8080 of the host machine, and has two web apps: one with the page /hello/hello.jsp that calculates 2 + 2 server-side with JSP, and another with /alexApp/alex that prints "Hello World" server-side.