https://fedorahosted.org/sssd/ticket/1249
The patch also reduces code duplication between several error handling
switch/case statements and fixes a bug in get_initgr where we would try
to cancel a transaction immediately after committing it.
Do we also want to canonicalize group names in a similar fashion? To be
honest, downloading the whole group twice just for the sake of
determining the correct group name seems a little too much to me..