Log any exceptions that occur in the tripleo.plan.update_from_dir action
Log any exceptions that occur in the tripleo.plan.update_from_dir action

Previously the action would return a string representation of the
exception. It will be unlikely that this would contain enough
information, so it is useful to log the full exception traceback.

Change-Id: Ibb5438470f7c4843c59a03640909bb82623f4046

openstack/tripleo-common,openstack/tripleo-common