Feature: Kerberos authentication in cumin
Reason: Some customers may want to use their kerberos auth server to handle cumin authentication.
Result (if any): By adding "kerb" to the "auth" config in cumin.conf and by setting kerberos_realm to the value required by their kerberos setup (krb5.conf), cumin will use the python-kerberos library to authenticate users. By default, all kerberos-authenticated users will be treated as non-admins in cumin. In order to get a kerberos-authenticated admin user, you would need to add an "external" user to the cumin datbase and then add the admin role assignment via the cumin-admin utility.