Title: #128: Fix group renaming issue when "id_provider = ldap" is set
Your version seems okay, please, force-push it to my branch.
Just a note: Although I do appreciate you took some time to come up with a better
solution, for the next time, if it's possible, I'd strongly prefer if you could
give me your suggestion and then I'd rework the patch ... that would help get a better
understanding of the parts that I'm still lacking knowledge in the project.
See the full comment at https://github.com/SSSD/sssd/pull/128#issuecomment-379716865