Description of problem:

The CLI should have the ability to get & set the Cinder's driver settings and configuration. At the moment, in order to change the configuration of a driver one should change the settings only through the cinder.conf file. 
This procedure is exposes the user to mistakes that might cause the service to crash without any good reason. 

To help the users configuring their Cinder back ends (single or multiple back ends) easily and with a check that the configuration input is valid for the driver that is been configured.