If the user gives any state other than the three given choices,
throw an error and print usage help. This helps avoid unacked msgs
that are stuck in the workflow queue cause problems.

With this change the argument only allows one of the 3 choices
It also takes a default value in case the arg is not given

* Update consume to accept new feature

* Move disconnect to callback

* Made use of exclusive queue

* Disconnect in message handlers

Since we are using exclusive queue, simply disconnect from it will
remove the queue

* Create a queuename variable based on the percent encoding of username.
* Pass 'queuename' attribute to add_user function.
* Create routing key based on 'queuename' rather then 'username'