DNSSEC: add debug mode to ldapkeydb.py
ldapkeydb.py can be executed directly now. In that case it will print
out key metadata as obtained using IPA LDAP API.
Kerberos credential cache has to be filled with principal posessing
appropriate access rights before the script is execured.
https://fedorahosted.org/freeipa/ticket/5348
Reviewed-By: Martin Basti <mbasti@redhat.com>