Making init keystone work

Calling os-cloud-config to init keystone.

Unmocking part of Heat calls, relation to plan will
not work unless we actually deploy a template created
by Tuskar-API. So mocking a relation and returning
always the first plan from plan-list.

Depends on https://review.openstack.org/#/c/113883/

Change-Id: I0a17eada05265d2bc4cc1ef6a611936522e9c6e9
Merge "Making init keystone work"