Satori Config may not include host_key

[Ziad Sawalha]

Simple discovery on satori without providing a host_key seems to break because the config namespace doesn't have a host_key:

$satori discovery.rackcloudtech.com
Traceback (most recent call last):
  File "/code/satori/.venv/bin/satori", line 10, in <module>
    sys.exit(main())
  File "/code/satori/satori/shell.py", line 127, in main
    results = discovery.run(args.netloc, args)
  File "/code/satori/satori/discovery.py", line 52, in run
    if all([config.system_info, config.host_key]):
AttributeError: 'Namespace' object has no attribute 'host_key'

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/79101

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/79101
Committed: https://git.openstack.org/cgit/stackforge/satori/commit/?id=e9a58e5e93ff0c1235d915c59665ddec430657e4
Submitter: Jenkins
Branch: master

commit e9a58e5e93ff0c1235d915c59665ddec430657e4
Author: Caleb Groom <email address hidden>
Date: Fri Mar 7 16:52:20 2014 -0600

    Fix crash on missing host_key

    Change-Id: If5dfbfd1a931d35755eeb2a1781fad46c56a173b
    Closes-Bug: #1289610