test runner testbed needs to handle floating ip for hpcloud

[Vincent Ladeuil]

Local testing for the testbed requires an IP than can be reached from a dev host.

For hpcloud that means creating a floating ip (http://docs.openstack.org/developer/python-novaclient/ref/v1_1/floating_ips.html) and adding it to the created nova instance (http://docs.openstack.org/developer/python-novaclient/ref/v1_1/servers.html ServerManager.add_floating_ip)

[Vincent Ladeuil (vila)]

'local testing' here means that a dev cannot use ./test_runner/tstrun/testbed.py from his machine as it will hang trying to connect to it (the test runner component being in the cloud is not affected).