fixed bug where exiting while in the rejoin code enter screen would poison the mutex

src/main.rs

@@ -127,7 +127,11 @@ fn handle_client(mut stream: TcpStream, channel: Channel, password: Option<Vec<u
                 i = 0;
                 continue 'bufreadloop;
             }
-            for user in &channel.lock().unwrap().online_users {
+            let users;
+            {
+                users = channel.lock().unwrap().online_users.clone();
+            }
+            for user in users {
                 if user.name == new_name {
                     if user.status == UserStatus::Disconnected {
                         stream