Description of problem:
Add the existing hbac service group 'Sudo' to a hbac rule. and it gets added as
'sudo'. This lists 'Sudo' in the 'Add' window. If selected, it will throw error
as expected - that this entry already exists. But this is inconsistent with
other 'Add' windows which do not list objects already added.

Also: when a hostgroup, or usergroup is added, the user or host 'Add' window
doesn't list members of groups already added. But Servicegroups and service
doesn't behave like that.

Version-Release number of selected component (if applicable):
ipa-server-2.2.0-16.el6.x86_64

How reproducible:
always

Steps to Reproduce:
1. Add 'Sudo' hbac service group
2. Add service
3. Click Add to add more service groups

Actual results:
2-> sudo services that are members of the Sudo Service group, are still listed
3 -> 'Sudo' is still listed as a group to add

Expected results:
2 -> sudo service group members should not be listed
3 -> Sudo should not be listed

Additional info: