Compatibility for CentrifyDC-krb5 package

The Centrify Kerberos client tools are no longer packaged with the Centrify Authentication Service, Privilege Elevation Service, and Audit & Monitoring Service agent or available from the Centrify Download Center. The client tools were formerly provided as a separate software package or as part of the core agent package to support Kerberos-based authentication on older operating systems. The package is no longer relevant on currently-supported operating systems.