Mark completed prompts

[Amhepel]

Prompts that have been completed should be highlighted in green.
Acceptance Test:

1. Open anyconnect and connect to vpn.buffalo.edu
2. open up terminal
3. ssh into cheshire (when connected into a UB network)
4. navigate to the directory /CSE442-542/2020-Fall/cse-442g/
5. run server using command "python server.py" in that terminal
6. On your main computer, open up another terminal and navigate to directory where the project is on your local machine.
7. Once in that directory, run "python Main.py"
8. When a user opens the application and clicks play to play the game, they will be able to move freely and interact with prompts
9. When a prompt has already been displayed once, it will show up as green when signaled again