Allow setup of credential encryption using fernet
Allow setup of credential encryption using fernet

With the addition of encrypted credential in keystone, we need to be able to
add setup steps in devstack to configure the credential repository with
encryption keys.

Depends-On: I97e7701bc5b8765d207cc721793643bcefa2d4e2
Depends-On: Id3e8922adc154cfec5f7a36613e22eb0b49eeffe
Change-Id: I433da9a257daa21ec3b5996b2bca571211f1fbba

richliu/devstack,dtroyer/devstack,noironetworks/devstack,bswartz/devstack,openstack-dev/devstack,richliu/devstack,noironetworks/devstack,group-policy/devstack,openstack-dev/devstack,dtroyer/devstack,bswartz/devstack,nawawi/openstack,group-policy/devstack,nawawi/openstack