very simple python grpc chat app. needs it to be done by 11:59pm EST on Feb 21nd.

1. User can sign up with a unique user id and password they can sign up with these . 2. List all user ids (or a subset of them, by text wildcard) 3. Send a message to a recipient. If the recipient is logged in, deliver immediately; otherwise queue the message and deliver on demand. If the message is sent to someone who isn't a user, return an error message. 4. Delete an account. Ask users to confirm if they attempt to delete an account that contains undelivered message. Needs it to be done by 11:59pm on Tuesday 21nd.