fixes nova_floating ip

* updates to nova_floating_ip:
  * delete floatingip
  * unassociate floatingip if instance is not found
  * cleanup
* updates to get_nodes to support nova
* refactor changes to work w/ oslab
* introduce retries to floatingip, ping, ssh

Change-Id: Id3d01f98cbf2027d7776df1cbfff1508c6d27b84
fail early if ssh open, but cloud-init failed

Ansible is already checking to see if the ssh port 22
is open, however many times cloud-init fails to run
properly and ssh will fail w/ {{ remote_user }}
This should catch that error early and fail the entire play

Change-Id: I76da1826cb5a5bcca22574bc32bf1299280884b5
remove comments and useless ssh test

Change-Id: I41ad5f0c735c4ff7b545fd06ca4106844b0e27d2
using the nova floating ip object is more reliable to remove ip

Change-Id: Ib3a4e1bab459dff8aae6405d5b04e756fa6dfadd
no need to fail on openstack-status

Change-Id: I84e729975816aa2f933e7a9c6b666d450db7c760
wait for openstack ports to open to test status

Change-Id: I0efcc7c9c56edb891f21fe02753d4423d86078cf