
  -spec unregister(RegName) -> true when RegName :: atom().

  Removes the registered name RegName associated with a process
  identifier or a port identifier from the name registry. For
  example:

    > unregister(db).
    true

  Keep in mind that you can still receive signals associated with
  the registered name after it has been unregistered as the sender
  may have looked up the name before sending to it.

  Users are advised not to unregister system processes.

  Failure: badarg if RegName is not a registered name.
