Modify the get console API

Changed the return value of the console GET api from string to
the following JSON object:
{'console_enabled': True, 'console_info': {'type': 'shellinaboxd',
   'url': 'http://<hostname>:<port>'}} for the node with console
enabled.
{'console_enabled': False, 'console_info': None} for the node
with console disabled.

Change-Id: I6c5818052e18ddfbcc148a18976ba5873b644039
Closes-Bug: 1307555
Implement list_instance_uuids() in Nova driver

This implements the list_instance_uuids() in the Nova
driver to help the compute manager more accurately track
instances running in an Ironic cluster.

Change-Id: I00978ea9622a2c15a6b2513bb11d695e7cab5572
Merge "Implement list_instance_uuids() in Nova driver"
Merge "Modify the get console API"