Cloned from https://bugzilla.redhat.com/show_bug.cgi?id=1193812
Description of problem:
When editing a host it's not possible to override puppet ca and puppetmaster if the hostgroup specifies these.

Version-Release number of selected component (if applicable):
6.0.7

How reproducible:
Every time

Steps to Reproduce:
1. Create a host group that specifies puppet ca and puppetmaster
2. Assign a host to that host group
3. Edit the host and try remove puppet ca and puppetmaster, click submit
4. The Puppet CA and puppetmaster values are back

Actual results:
The values are still set.

Expected results:
It should be possible to override these values on host level.

Additional info:
Assigning the host to another host group that does not specify puppet ca or puppetmaster works as expected.