[lab3 Exercise 3] Change ProfileAPIServer in profile-server.py to avoid
                  running as root.
[lab3 Exercise 4] Build my-profile to implement some interesting
                  features.
[lab3 Challenge] 1. Create an RPC server that is in charge of modifying
                    user profiles, and which requires a valid user token
                    in order to modify a user's profile.
                 2. Change the rest of the Zoobar application code to
                    modify user profiles via this RPC server.