Refactorise Keystone resources management
Refactorise Keystone resources management

Refactorise the code of Keystone resources management with backward
compatibility since we don't modify the unit tests.

Change-Id: I8fc27ea6cc49a4c0c518f7314b3277d6980491b4
Implements: blueprint common-openstack-identity-resource

openstack/puppet-neutron,redhat-cip/puppet-neutron,aldavud/puppet-neutron,cloudbuy/puppet-neutron,fuel-infra/puppet-neutron,CiscoSystems/puppet-neutron,fuel-infra/puppet-neutron,redhat-cip/puppet-neutron,aldavud/puppet-neutron,aldavud/puppet-neutron,fuel-infra/puppet-neutron,IPnett/puppet-neutron,plumgrid/puppet-neutron,IPnett/puppet-neutron,CiscoSystems/puppet-neutron,NeCTAR-RC/puppet-neutron,rdo-puppet-modules/puppet-neutron,openstack/puppet-neutron,plumgrid/puppet-neutron,cloudbuy/puppet-neutron,IPnett/puppet-neutron,NeCTAR-RC/puppet-neutron,CiscoSystems/puppet-neutron,rdo-puppet-modules/puppet-neutron,NeCTAR-RC/puppet-neutron,redhat-cip/puppet-neutron,cloudbuy/puppet-neutron