Ui improvements

see https://github.com/theforeman/staypuft/wiki/UI-Parameters-for-new-wizard
cc @sseago 
**NOT READY**
I wonder if what's missing is just default values (this will be true for the step 3 stuff too) -- I haven't looked at the code for the form in detail yet, but this shouldn't depend on any seed data. Once the these new params are set on the deployment, the form should be picking them up -- and on submit, setting them -- but we do need to make sure the defaults match expectations.