(feat) added eval, results reporting, general fixes (MVP)

This code: 
 - evaluates code sent to the server 
 - server returns the result of the code as well as the score to user as soon as code is submitted
 - when code it submitted for both users, it assesses a winner and reports to both users
 - destroys prompts when one user in a room logs out, generates a new prompt when a new user logs in (bugfix)