Have inventory use os-client-config extra_config
Have inventory use os-client-config extra_config

There are some additional inventory behaviors that need to be configured
in clouds.yaml, which means we need to allow them to be requested by the
inventory class.

Change-Id: I6f09d73422163e54776d03ead1d83322b6fdccf5

openstack/python-openstacksdk,stackforge/python-openstacksdk,stackforge/python-openstacksdk,openstack/python-openstacksdk,openstack-infra/shade,dtroyer/python-openstacksdk,openstack-infra/shade,dtroyer/python-openstacksdk