[SSSD] [sssd PR#336][opened] idmap_error_string: add missing descriptions

[sumit-bose]

   URL: https://github.com/SSSD/sssd/pull/336
Author: sumit-bose
 Title: #336: idmap_error_string: add missing descriptions
Action: opened

PR body:
"""
Related to https://fedorahosted.org/sssd/ticket/1960
Related to https://fedorahosted.org/sssd/ticket/1938
Related to https://fedorahosted.org/sssd/ticket/1844
Related to https://fedorahosted.org/sssd/ticket/1593
"""

To pull the PR as Git branch:
git remote add ghsssd https://github.com/SSSD/sssd
git fetch ghsssd pull/336/head:pr336
git checkout pr336