Use cinder_config for cinder keystone auth credentials

No longer placing values in api-paste.ini

Cinder part of this bug
https://bugzilla.redhat.com/show_bug.cgi?id=888725

Change-Id: I0167fe0df534514d617564e70f23805a86587945
Merge "Use cinder_config for cinder keystone auth credentials" into folsom