use show_instance for nova.create
cleanup nova driver using show_instance

There isn't a reason to use list_nodes_full just to find information about the
cloud server.  It is already done to see if it the server already exists in the
salt.cloud.CloudClient to make sure one in the environment doesn't already
exist with that name.
use show_instance for openstack driver too

show_instance for libcloud uses list_node_full already
Be consistent on state/status

Turns out libcloud needs it to be state, instead of status of the server
slice.  Should be set now
Set log level for requests in novaclient to WARNING

Just need to get rid of the stupid starting https connection message on
every requests connection in novaclient.  It can be set in the __opts__,
but will be documented when the change in made later.
return empty dict if server_show_libcloud fails

Should be an empty list, if it returns an index error, it means no
servers were matched.
Merge pull request #12871 from gtmanfred/nova

Switch openstack drivers to useing show_instance