Actually exit from the app when we're done cleaning up.

src/main.ts

@@ -35,6 +35,7 @@ function clean_up() {
 		writeFileSync(`${db_dir}/${code}`, active_games[code].toJSON());
 	};
 	log.info(`Finished saving games to disk.`);
+	process.exit(0);
 }
 
 // Listen to the signals for the cleanup requirement