A few fixes to the updated wizard step 1:

- renamed "HA" attribute "LayoutName" -- right now the layouts are HA vs.
  non-HA, but it's possible that additional reference architectures will be
  generated that might add to the layout list, so I didn't want to design
  ourselves into a corner with a boolean HA/non-HA model. In addition, we need
  the selection value to match the Layout name, since that's how we query the
  layout to find it. Layout is unique on (name, networking), so those two values
  should be the ones that are set as the UI param values. Values now match
  what's shown in the UI (and in the updated seeds.rb) rather than true and false
- fixed typo Staypuft::Deployment::Networking::NOVA as 'nova' rather than 'nove'
- re-enabled update_hostgroup_list. We can't use lazy evaluation here like we
  do for params whose actions are only to set class params, since in response
  to the layout-related params, we have to actually create Hostgroups. This
  method is now triggered by the UI param selections, though.
- AMQP Provider is now a hidden UI param -- the backend still requires this
  setting, so the only reason it's out-of-scope in the UI is that Qpid is
  currently broken on the back end. With this setup, all we need to do to
  re-enable is to un-hide the form element.
- default values weren't being set properly for the new params; added a
  before_validation callback to set these
- moved some additional logic from the new action in the deployments_controller
  to this new callback
- some updates to the functional_dependencies seeds.rb bits:
  - Don't repeat the puppclass-level quickstack::pacemaker::params, put both
    entries under the same top level item
  - Added settings for amqp_server/amqp_provider