Hi,
Usergroup's configuration are modified by the api method hostrgroup.create.

Steps to reproduce:

1. Create a usergroup test with All groups RO or RW
2. Create new hostgroup via API or webUI
3. Check the usergroup rights they change for all groups  except the hostgroup just create.

Result:
See screenshots:

•  step1 usergroup configuration before create new hostgroup
•  step2 usergroup configuration after create hostgroup

Expected

Usergroup's configuration don't change when a hostgroup has been created, it conserve rights on `All groups`