When selinux does not work in the environment, but SSSD was built with libsemanage support then sss_userdel may not be able to delete users previously added with sss_useradd.

How to reproduce:
1. add user with sss_useradd

• first the user is added to sysdb and then the libsemanage part is called, if the
  libsemanage part fails, the operation fails, but user is not deleted from sysdb.

1. try to delete user with sss_userdel

• the libsemanage operations are performed before the user is deleted from sysdb. If the libsemanage operation fails, the tool never proceeds to removal of the user from sysdb. So the user is never deleted.

NOTE: It is reproducible in our current CI (2015-10-22) when CI is built with libsemanage support. But it can happen anytime when selinux operation fails during useradd or userdel.

Possible solutions:

• In useradd, delete the added user from sysdb if selinux operation fails.
• In userdel, add --force option that will delete the user even if selinux operations fail